diff --git a/README.md b/README.md
index 23c05c3..a1cb919 100644
--- a/README.md
+++ b/README.md
@@ -215,4 +215,4 @@ im `pom.xml` if you are having problems building locally!
 You will need Maven >= 3.3.9 which on RHEL/CentOS system can be obtained via
 SoftwareCollections:
 
-    scl enable rh-maven35 /bin/bash
+    scl enable rh-maven36 /bin/bash
diff --git a/src/main/java/org/kiwitcms/java/api/RpcClient.java b/src/main/java/org/kiwitcms/java/api/RpcClient.java
index 9eee90e..1266be1 100644
--- a/src/main/java/org/kiwitcms/java/api/RpcClient.java
+++ b/src/main/java/org/kiwitcms/java/api/RpcClient.java
@@ -1,5 +1,5 @@
 // Copyright (c) 2018-2019 Aneta Petkova <aneta.v.petkova@gmail.com>
-// Copyright (c) 2019-2020 Alexander Todorov <atodorov@MrSenko.com>
+// Copyright (c) 2019-2021 Alexander Todorov <atodorov@MrSenko.com>
 
 // Licensed under the GPLv3: https://www.gnu.org/licenses/gpl.html
 
@@ -296,7 +296,7 @@ public Product createNewProduct(String name) {
         Object classificationId = ((JSONObject) jsonArray.get(0)).get("id");
 
         params.put("name", name);
-        params.put("classification_id", classificationId);
+        params.put("classification", classificationId);
 
         JSONObject json = (JSONObject) executeViaPositionalParams(CREATE_PRODUCT_METHOD, Arrays.asList((Object) params));
         try {
diff --git a/src/main/java/org/kiwitcms/java/model/TestCase.java b/src/main/java/org/kiwitcms/java/model/TestCase.java
index 50c341b..c24a570 100644
--- a/src/main/java/org/kiwitcms/java/model/TestCase.java
+++ b/src/main/java/org/kiwitcms/java/model/TestCase.java
@@ -1,5 +1,5 @@
 // Copyright (c) 2018-2019 Aneta Petkova <aneta.v.petkova@gmail.com>
-// Copyright (c) 2020 Alexander Todorov <atodorov@MrSenko.com>
+// Copyright (c) 2020-2021 Alexander Todorov <atodorov@MrSenko.com>
 
 // Licensed under the GPLv3: https://www.gnu.org/licenses/gpl.html
 
@@ -39,7 +39,7 @@ public Date getCreateDate() {
         return createDate;
     }
 
-    @JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "yyyy-MM-dd HH:mm:ss")
+    @JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "yyyy-MM-dd'T'HH:mm:ss.SSS")
     @JsonSetter("create_date")
     public void setCreateDate(Date createDate) {
         this.createDate = createDate;
diff --git a/src/main/java/org/kiwitcms/java/model/TestPlan.java b/src/main/java/org/kiwitcms/java/model/TestPlan.java
index bb3856f..919b81f 100644
--- a/src/main/java/org/kiwitcms/java/model/TestPlan.java
+++ b/src/main/java/org/kiwitcms/java/model/TestPlan.java
@@ -1,5 +1,5 @@
 // Copyright (c) 2018-2019 Aneta Petkova <aneta.v.petkova@gmail.com>
-// Copyright (c) 2020 Alexander Todorov <atodorov@MrSenko.com>
+// Copyright (c) 2020-2021 Alexander Todorov <atodorov@MrSenko.com>
 
 // Licensed under the GPLv3: https://www.gnu.org/licenses/gpl.html
 
@@ -52,7 +52,7 @@ public String getCreateDate() {
         return createDate;
     }
 
-    @JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "yyyy-MM-dd HH:mm:ss")
+    @JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "yyyy-MM-dd'T'HH:mm:ss.SSS")
     @JsonSetter("create_date")
     public void setCreateDate(String createDate) {
         this.createDate = createDate;
diff --git a/src/main/java/org/kiwitcms/java/model/TestRun.java b/src/main/java/org/kiwitcms/java/model/TestRun.java
index 3746618..3c4c34e 100644
--- a/src/main/java/org/kiwitcms/java/model/TestRun.java
+++ b/src/main/java/org/kiwitcms/java/model/TestRun.java
@@ -1,5 +1,5 @@
 // Copyright (c) 2018-2019 Aneta Petkova <aneta.v.petkova@gmail.com>
-// Copyright (c) 2020 Alexander Todorov <atodorov@MrSenko.com>
+// Copyright (c) 2020-2021 Alexander Todorov <atodorov@MrSenko.com>
 
 // Licensed under the GPLv3: https://www.gnu.org/licenses/gpl.html
 
@@ -39,7 +39,7 @@ public int getPlan() {
         return plan;
     }
 
-    @JsonSetter("plan_id")
+    @JsonSetter("plan")
     public void setPlan(int plan) {
         this.plan = plan;
     }
@@ -48,7 +48,7 @@ public int getBuild() {
         return build;
     }
 
-    @JsonSetter("build_id")
+    @JsonSetter("build")
     public void setBuild(int build) {
         this.build = build;
     }