Link malfunction, ghost rooms

[Kroepoek]

For some weeks now we have problems with our link. With the same link / meeting ID people end up in different rooms randomly. Even if they log off and on again we don't seem to be able to get everyone into the same room. This is strange since everyone uses the same link that we send in a WhatsApp group app. We can't see who ends up where. 

What can we do?