I've got a sudden issue with calls not working anymore with my Galaxy S8. Strangely enought Text and Internet Data are fine.
I've tried switching Sim Cards and the phone itself is fine as the sim from another provider is working fine in the S8. The sim from Lebara/Vodaphone which is causing problems with the S8 is working fine in a Galaxy S7.
I've been in contact with support from Lebara and they've asked me to get another sim for them to port my number to.
This didn't solve the problem. I've also done a factory reset on the S8 to no avail.
Any ideas what might be causing this?