UCB build error with Simple IAP System

Hi I am getting the following error, but only on cloud builds (ios and android )

17552: [Unity] Type '[Assembly-CSharp]SIS.IAPObject' has an extra field 'storeIDs' of type 'System.Collections.Generic.List`1[UnityEngine.Purchasing.StoreID]' in the player and thus can't be serialized (expected 'title' of type 'System.String')
17553: [Unity] UnityEditor.BuildPipeline:BuildPlayerInternalNoCheck(String[], String, String, BuildTargetGroup, BuildTarget, BuildOptions, Boolean)
17554: [Unity] UnityEditor.CloudBuild.Builder:Build()
17555: [Unity] Type '[Assembly-CSharp]SIS.IAPObject' has an extra field 'type' of type 'UnityEngine.Purchasing.ProductType' in the player and thus can't be serialized (expected 'title' of type 'System.String')
17556: [Unity] UnityEditor.BuildPipeline:BuildPlayerInternalNoCheck(String[], String, String, BuildTargetGroup, BuildTarget, BuildOptions, Boolean)
17557: [Unity] UnityEditor.CloudBuild.Builder:Build()
17558: [Unity] Fields serialized in Editor, class 'SIS.IAPObject'
17559: [Unity] 'id' of type 'System.String'
17560: [Unity] 'type' of type 'SIS.ProductType'
17561: [Unity] 'title' of type 'System.String'
17562: [Unity] 'description' of type 'System.String'
17563: [Unity] 'realPrice' of type 'System.String'
17564: [Unity] 'fetch' of type 'System.Boolean'
17565: [Unity] 'icon' of type 'UnityEngine.Sprite'
17566: [Unity] 'usageCount' of type 'System.Int32'
17567: [Unity] 'virtualPrice' of type 'System.Collections.Generic.List`1[SIS.IAPCurrency]'
17568: [Unity] 'req' of type 'SIS.IAPRequirement'
17569: [Unity] 'editorType' of type 'SIS.IAPType'
17570: [Unity] 'platformFoldout' of type 'System.Boolean'
17571: [Unity] UnityEditor.BuildPipeline:BuildPlayerInternalNoCheck(String[], String, String, BuildTargetGroup, BuildTarget, BuildOptions, Boolean)
17572: [Unity] UnityEditor.CloudBuild.Builder:Build()
17573: [Unity] Fields serialized in target platform, class 'SIS.IAPObject'
17574: [Unity] 'id' of type 'System.String'
17575: [Unity] 'storeIDs' of type 'System.Collections.Generic.List`1[UnityEngine.Purchasing.StoreID]'
17576: [Unity] 'type' of type 'UnityEngine.Purchasing.ProductType'
17577: [Unity] 'title' of type 'System.String'
17578: [Unity] 'description' of type 'System.String'
17579: [Unity] 'realPrice' of type 'System.String'
17580: [Unity] 'fetch' of type 'System.Boolean'
17581: [Unity] 'icon' of type 'UnityEngine.Sprite'
17582: [Unity] 'usageCount' of type 'System.Int32'
17583: [Unity] 'virtualPrice' of type 'System.Collections.Generic.List`1[SIS.IAPCurrency]'
17584: [Unity] 'req' of type 'SIS.IAPRequirement'
17585: [Unity] 'editorType' of type 'SIS.IAPType'
17586: [Unity] 'platformFoldout' of type 'System.Boolean'
17587: [Unity] UnityEditor.BuildPipeline:BuildPlayerInternalNoCheck(String[], String, String, BuildTargetGroup, BuildTarget, BuildOptions, Boolean)
17588: [Unity] UnityEditor.CloudBuild.Builder:Build()
17589: [Unity] Error building player because script class layout is incompatible between the editor and the player.
17590: [Unity] (Filename: Line: -1)

Works fine with local builds. What I don't understand is how that error can even be possible. I forced clean builds as well. Any help would be greatly appreciated.

Thanks