Hi @tomek1_1988,
Unfortunately this functionality is wholly implemented by an external company, and we will have to contact them to ask for more details. It would be helpful if you could provide the exact error code which comes up in Mervis, and possibly a screenshot as well.
I will try to get back to you with an answer within a few weeks, but you may find it easier to investigate the issue yourself in the meantime.
Sincere apologies