Speedport and cloud manager

in CloudManager
Hello
Anyone else facing the same issue ?
on sights where the client has only the provider router , typicaly a speedport , the access point show online for 5-10 minutes and then goes offline
This happens on diferent isps so its not an isp issue but allways with the same type of router which
is speedport entry i2
no matter what ports we open , even with disabled firewall we still getting the same behavior
anyone else having this issue?