I have an api that pushes salesorders and it works if I set the version to 18.200.001.
When I move it to 20.200.001 it fails with the error
[message] => An error has occurred.
[exceptionMessage] => Sequence contains no matching element
[exceptionType] => System.InvalidOperationException
[stackTrace] => at System.Linq.Enumerable.Single[TSource](IEnumerable`1 source, Func`2 predicate)
at PX.Api.ContractBased.EntityExportContextBuilder.ExtractFieldMappingKeyForDetail(String mappingKey, EntityField field, EntityMappingProjection[] entityFields, IMetadataProvider metadataProvider, IEntityMappingKeyService entityMappingKeyService, String endpointName, String version) in C:\build\code_repo\NetTools\PX.Api.ContractBased\EntityExportContextBuilder.cs:line 1343
The only information I can find about changes is on page 55 of https://www.acumatica.com/media/2020/09/AcumaticaERP_IntegrationDevelopmentGuide.pd
Where it says
‘
• The type of the Payments field is changed.
• Mapping has changed
‘
After I get this working I do plan to get it to the latest version available ( "22.200.001")