Unable to add indexers to sonarr v3

[Drapersniper]

NZBHydra2 error messages

Error: Object reference not set to an instance of an object
Unexpected error: Sonarrv3 returned error message: Object reference not set to an instance of an object

Sonarr error message

Request Failed. POST /api/v3/indexer: Object reference not set to an instance of an object


System.NullReferenceException: Object reference not set to an instance of an object
  at Sonarr.Http.ClientSchema.SchemaBuilder.ReadFromSchema (System.Collections.Generic.List`1[T] fields, System.Type targetType) [0x000a7] in <8453225475534ad28c8bd36c6df56787>:0 
  at Sonarr.Api.V3.ProviderResourceMapper`2[TProviderResource,TProviderDefinition].ToModel (TProviderResource resource) [0x000d9] in <43a55d1ec54a4547a03949ac2897b286>:0 
  at Sonarr.Api.V3.Indexers.IndexerResourceMapper.ToModel (Sonarr.Api.V3.Indexers.IndexerResource resource) [0x00005] in <43a55d1ec54a4547a03949ac2897b286>:0 
  at Sonarr.Api.V3.ProviderModuleBase`3[TProviderResource,TProvider,TProviderDefinition].GetDefinition (TProviderResource providerResource, System.Boolean includeWarnings, System.Boolean validate) [0x00000] in <43a55d1ec54a4547a03949ac2897b286>:0 
  at Sonarr.Api.V3.ProviderModuleBase`3[TProviderResource,TProvider,TProviderDefinition].CreateProvider (TProviderResource providerResource) [0x00000] in <43a55d1ec54a4547a03949ac2897b286>:0 
  at Sonarr.Http.REST.RestModule`1[TResource].<set_CreateResource>b__42_0 (System.Object options) [0x0000e] in <8453225475534ad28c8bd36c6df56787>:0 
  at Nancy.NancyModule+<>c__DisplayClass38_0`1[T].<Post>b__0 (System.Object args) [0x00047] in <e31b230dbd29407fadcc55713e0bbd0f>:0 
  at Nancy.NancyModule+<>c__DisplayClass40_0`1[T].<Post>b__0 (System.Object args, System.Threading.CancellationToken ct) [0x00047] in <e31b230dbd29407fadcc55713e0bbd0f>:0 
  at Nancy.Routing.Route`1[T].Invoke (Nancy.DynamicDictionary parameters, System.Threading.CancellationToken cancellationToken) [0x00017] in <e31b230dbd29407fadcc55713e0bbd0f>:0 
  at Nancy.Routing.DefaultRouteInvoker.Invoke (Nancy.Routing.Route route, System.Threading.CancellationToken cancellationToken, Nancy.DynamicDictionary parameters, Nancy.NancyContext context) [0x00086] in <e31b230dbd29407fadcc55713e0bbd0f>:0 
  at Nancy.Routing.DefaultRequestDispatcher.Dispatch (Nancy.NancyContext context, System.Threading.CancellationToken cancellationToken) [0x002b7] in <e31b230dbd29407fadcc55713e0bbd0f>:0 
  at Nancy.NancyEngine.InvokeRequestLifeCycle (Nancy.NancyContext context, System.Threading.CancellationToken cancellationToken, Nancy.Bootstrapper.IPipelines pipelines) [0x0011d] in <e31b230dbd29407fadcc55713e0bbd0f>:0 

Sonarr is running the most recent develop branch (hotio nightly image), - that being said it is a custom image but there's been no changes to the APIs on it.

Version 3.9.9.9999
Package Version 3.0.6.1451 by Hotio/Draper
Mono Version 6.12.0.122