Rest API can't able to update customer throws the error.

[kirtinariya1]

Magento 2.3.0 rest API can't able to update customer throws the error.
API /V1/customers/:customerId
Method: PUT
URL: http://localhost/magentosample230/rest/V1/customers/2

Preconditions (*)

1. Magento 2.3.0 & 2.3-develop

Steps to reproduce (*)

1. Run the customer update API.
2. Method: PUT
3. Headers: Authorization:Bearer yfhwg1j458dw086qelbqkkkmp6f0tj89
Content-Type:application/json
4. Body:

{
      "customer": {
      "email": "john@gmail.com",
      "firstname": "firstname new",
      "lastname": "lastname new",
      "website_id": 1
   }
}

5. URL: http://localhost/magentosample230/rest/V1/customers/2

Expected result (*)

1. Customer should be updated and reponse will return success message.

Actual result (*)

1. Throw the error in response.
   Error:

{
    "message": "A customer with the same email address already exists in an associated website.",
    "trace": "#0 /var/www/html/magentosample230/vendor/magento/module-eav/Model/Entity/VersionControl/AbstractEntity.php(90): Magento\\Customer\\Model\\ResourceModel\\Customer->_beforeSave(Object(Magento\\Customer\\Model\\Customer\\Interceptor))\n#1 /var/www/html/magentosample230/vendor/magento/framework/Interception/Interceptor.php(58): Magento\\Eav\\Model\\Entity\\VersionControl\\AbstractEntity->save(Object(Magento\\Customer\\Model\\Customer\\Interceptor))\n#2 /var/www/html/magentosample230/vendor/magento/framework/Interception/Interceptor.php(138): Magento\\Customer\\Model\\ResourceModel\\Customer\\Interceptor->___callParent('save', Array)\n#3 /var/www/html/magentosample230/vendor/magento/framework/App/Cache/FlushCacheByTags.php(68): Magento\\Customer\\Model\\ResourceModel\\Customer\\Interceptor->Magento\\Framework\\Interception\\{closure}(Object(Magento\\Customer\\Model\\Customer\\Interceptor))\n#4 /var/www/html/magentosample230/vendor/magento/framework/Interception/Interceptor.php(135): Magento\\Framework\\App\\Cache\\FlushCacheByTags->aroundSave(Object(Magento\\Customer\\Model\\ResourceModel\\Customer\\Interceptor), Object(Closure), Object(Magento\\Customer\\Model\\Customer\\Interceptor))\n#5 /var/www/html/magentosample230/vendor/magento/framework/Interception/Interceptor.php(153): Magento\\Customer\\Model\\ResourceModel\\Customer\\Interceptor->Magento\\Framework\\Interception\\{closure}(Object(Magento\\Customer\\Model\\Customer\\Interceptor))\n#6 /var/www/html/magentosample230/generated/code/Magento/Customer/Model/ResourceModel/Customer/Interceptor.php(117): Magento\\Customer\\Model\\ResourceModel\\Customer\\Interceptor->___callPlugins('save', Array, NULL)\n#7 /var/www/html/magentosample230/vendor/magento/framework/Model/AbstractModel.php(648): Magento\\Customer\\Model\\ResourceModel\\Customer\\Interceptor->save(Object(Magento\\Customer\\Model\\Customer\\Interceptor))\n#8 /var/www/html/magentosample230/vendor/magento/framework/Interception/Interceptor.php(58): Magento\\Framework\\Model\\AbstractModel->save()\n#9 /var/www/html/magentosample230/vendor/magento/framework/Interception/Interceptor.php(138): Magento\\Customer\\Model\\Customer\\Interceptor->___callParent('save', Array)\n#10 /var/www/html/magentosample230/vendor/magento/framework/Interception/Interceptor.php(153): Magento\\Customer\\Model\\Customer\\Interceptor->Magento\\Framework\\Interception\\{closure}()\n#11 /var/www/html/magentosample230/generated/code/Magento/Customer/Model/Customer/Interceptor.php(1118): Magento\\Customer\\Model\\Customer\\Interceptor->___callPlugins('save', Array, Array)\n#12 /var/www/html/magentosample230/vendor/magento/module-customer/Model/ResourceModel/CustomerRepository.php(219): Magento\\Customer\\Model\\Customer\\Interceptor->save()\n#13 /var/www/html/magentosample230/vendor/magento/framework/Interception/Interceptor.php(58): Magento\\Customer\\Model\\ResourceModel\\CustomerRepository->save(Object(Magento\\Customer\\Model\\Data\\Customer), NULL)\n#14 /var/www/html/magentosample230/vendor/magento/framework/Interception/Interceptor.php(138): Magento\\Customer\\Model\\ResourceModel\\CustomerRepository\\Interceptor->___callParent('save', Array)\n#15 /var/www/html/magentosample230/vendor/vertex/module-tax/Model/Plugin/CustomerRepositoryPlugin.php(179): Magento\\Customer\\Model\\ResourceModel\\CustomerRepository\\Interceptor->Magento\\Framework\\Interception\\{closure}(Object(Magento\\Customer\\Model\\Data\\Customer), NULL)\n#16 /var/www/html/magentosample230/vendor/magento/framework/Interception/Interceptor.php(135): Vertex\\Tax\\Model\\Plugin\\CustomerRepositoryPlugin->aroundSave(Object(Magento\\Customer\\Model\\ResourceModel\\CustomerRepository\\Interceptor), Object(Closure), Object(Magento\\Customer\\Model\\Data\\Customer), NULL)\n#17 /var/www/html/magentosample230/vendor/magento/module-customer/Model/Plugin/CustomerRepository/TransactionWrapper.php(44): Magento\\Customer\\Model\\ResourceModel\\CustomerRepository\\Interceptor->Magento\\Framework\\Interception\\{closure}(Object(Magento\\Customer\\Model\\Data\\Customer), NULL)\n#18 /var/www/html/magentosample230/vendor/magento/framework/Interception/Interceptor.php(135): Magento\\Customer\\Model\\Plugin\\CustomerRepository\\TransactionWrapper->aroundSave(Object(Magento\\Customer\\Model\\ResourceModel\\CustomerRepository\\Interceptor), Object(Closure), Object(Magento\\Customer\\Model\\Data\\Customer), NULL)\n#19 /var/www/html/magentosample230/vendor/magento/framework/Interception/Interceptor.php(153): Magento\\Customer\\Model\\ResourceModel\\CustomerRepository\\Interceptor->Magento\\Framework\\Interception\\{closure}(Object(Magento\\Customer\\Model\\Data\\Customer), NULL)\n#20 /var/www/html/magentosample230/generated/code/Magento/Customer/Model/ResourceModel/CustomerRepository/Interceptor.php(26): Magento\\Customer\\Model\\ResourceModel\\CustomerRepository\\Interceptor->___callPlugins('save', Array, NULL)\n#21 [internal function]: Magento\\Customer\\Model\\ResourceModel\\CustomerRepository\\Interceptor->save(Object(Magento\\Customer\\Model\\Data\\Customer), NULL)\n#22 /var/www/html/magentosample230/vendor/magento/module-webapi/Controller/Rest/SynchronousRequestProcessor.php(95): call_user_func_array(Array, Array)\n#23 /var/www/html/magentosample230/vendor/magento/module-webapi/Controller/Rest.php(188): Magento\\Webapi\\Controller\\Rest\\SynchronousRequestProcessor->process(Object(Magento\\Framework\\Webapi\\Rest\\Request\\Proxy))\n#24 /var/www/html/magentosample230/vendor/magento/framework/Interception/Interceptor.php(58): Magento\\Webapi\\Controller\\Rest->dispatch(Object(Magento\\Framework\\App\\Request\\Http))\n#25 /var/www/html/magentosample230/vendor/magento/framework/Interception/Interceptor.php(138): Magento\\Webapi\\Controller\\Rest\\Interceptor->___callParent('dispatch', Array)\n#26 /var/www/html/magentosample230/vendor/magento/framework/Interception/Interceptor.php(153): Magento\\Webapi\\Controller\\Rest\\Interceptor->Magento\\Framework\\Interception\\{closure}(Object(Magento\\Framework\\App\\Request\\Http))\n#27 /var/www/html/magentosample230/generated/code/Magento/Webapi/Controller/Rest/Interceptor.php(26): Magento\\Webapi\\Controller\\Rest\\Interceptor->___callPlugins('dispatch', Array, Array)\n#28 /var/www/html/magentosample230/vendor/magento/framework/App/Http.php(135): Magento\\Webapi\\Controller\\Rest\\Interceptor->dispatch(Object(Magento\\Framework\\App\\Request\\Http))\n#29 /var/www/html/magentosample230/generated/code/Magento/Framework/App/Http/Interceptor.php(24): Magento\\Framework\\App\\Http->launch()\n#30 /var/www/html/magentosample230/vendor/magento/framework/App/Bootstrap.php(258): Magento\\Framework\\App\\Http\\Interceptor->launch()\n#31 /var/www/html/magentosample230/index.php(39): Magento\\Framework\\App\\Bootstrap->run(Object(Magento\\Framework\\App\\Http\\Interceptor))\n#32 {main}"
}

[m2-assistant]

Hi @kirtinariya1. Thank you for your report.
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Please make sure that the issue is reproducible on the vanilla Magento instance following Steps to reproduce. To deploy vanilla Magento instance on our environment, please, add a comment to the issue:

@magento give me 2.3-develop instance - upcoming 2.3.x release

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@kirtinariya1 do you confirm that you were able to reproduce the issue on vanilla Magento instance following steps to reproduce?

• yes
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[m2-assistant]

Hi @engcom-Charlie. Thank you for working on this issue.
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[magento-engcom-team]

✅ Confirmed by @engcom-Charlie
Thank you for verifying the issue. Based on the provided information internal tickets MC-20196 were created

Issue Available: @engcom-Charlie, You will be automatically unassigned. Contributors/Maintainers can claim this issue to continue. To reclaim and continue work, reassign the ticket to yourself.

[jmcharadva]

@kirtinariya1
Can you please check with below mentioned parameter?
{
"customer": {
"id":1,
"email": "your@email.com",
"firstname": "firstname new",
"lastname": "lastname new",
"website_id": 1
}
}

[engcom-Charlie]

@jmcharadva thanks for contributing!

@kirtinariya1 you have to write customer id in your request body
Swagger: