I want to import records into Dynamics, like I have done many times before. But currently it's no longer possible, the import status is Sent, doesn't change to another status and the number of all completed and failed records is shown as 0. Regardless the entity (for example Contacts), I can export to Excel, but importing a file (even that same unchanged file gives the same result: Import status = Sent.
I may have changed something unintended, but I have no idea how to fix this issue. I made a copy to my Sandbox environment to try a few things, but the same happens no matter what I do.
I hope you can support me to find a solution for this issue.