Data source for dataset with incremental refresh cannot be updated via REST API

Hi @yingyinr,
Thanks for your answer.
Nothing from mentioned limitations is related to my dataset.
XMLA endpoints wern't used.
Data source is SQL server.
There are no parameters in connection details: just plain server address and DB name.
Also, there was mentioned that "The original data source and the new data source must have the exact same schema."
Not sure what it means, but seems to be not related to my case.
Here are API endpoints that I execute:
Retrieving of existing datasources:

Updating this datasource via UpdateDatasource endpoint:

Retrieving datasources after update:

As a result a new datasource was added instead of updating of existing one.
I also checked the same report without incremental refresh.
It works as expected. The existing datasource is updated.