Telephone call limits

Hello,
We used meet.jit.si for a meeting but one person who was connected via telephone was disconnected after two hours.
When she tried to call again, it never worked again.
Is there a limit for calls from a landline or mobile?

Thank you for your answers.

Best regards,

Pierre S

The limit is 6 hours. You can send me that persons number in a private message to check for some problems on our side.