Yes I have, but there is something wrong with my database it seems. I think there was an error during one of the schema updates. This seems to be causing the troubles (I have not been adding users for months due to a spam attack).
2020-08-18 22:19:29.802644+02:00 [error] <0.457.0>@ejabberd_sql:check_error/2:1236 SQL query 'INSERT INTO users(username, password) VALUES ('proact6', '6b8a3278a4b4ac1d');' failed: "#HY000Field 'serverkey' doesn't have a default value"
Or could it be due to the fact I use plain passwords in the DB still? I should move to encrypted ones… if so then this will be my next step.