Connection error using SIM Card

Hi all,
since a few days we have some issues around the world when our users need to use their SIM Cards.
ZCC is not able to establish a connection towards the ZCloud.
This issue is with different SIM Card providers from Germany, Italy etc.
We figured out, if you use the SIM Card in another Notebook, the issue is following the SIM Card.

In Germany we also discovered if some users are customer of Deutsche Telekom and using the new Router from Telekom there is a feature called LTE Bonding, something like “lite SDWAN”. The LTE and WAN connection are used simultaneously. If you disable this feature, everything is working fine.

We already have multipe open Tickets with Zscaler but no resulution.

Is anyone else facing similar issues when using the SIM Card connection in a Notebook and maybe have a fix/solution/workaround?

Cheers Jonas