WDM 5.7.3 multiple Enterprise licences can not be added

I have migrated WDM to a new 2016 server

Name and ip are identical to the old server

All lights green ... no problem so far

We have purchased 8 Enterprise sale keys in the past

Adding the first key is no problem

Second key generates message that evaluation key wil be removed when added

If you click no nothing happens

If you click yes the first sale key will be removed and replaced with the second key ...

Seems problem with database

Any idea how to solve this bug ?