Other Last line not available??

[systemind]

Hello! Every time I try to call someone using my new iPhone XS Max I get a message saying last line not available. I’ve never seen this before on an iPhone ever. I received the phone today and put in the SIM card from my old iPhone 8 Plus. I’m on T-Mobile. Does anyone has any ideas? Thanks in advanced.

 

[maflynn]

Call your carrier

 

[systemind]

For those wondering this is ebag T-Mobile said

 

[systemind]

I find it crazy that no one knows about this issue and google shows absolutely nothing regarding this message!

 

[ZackaryScott]

Same here. I have Verizon.