Can't set my service tag

I am unable to set my service tag in Halo Infinite. I get a message that says “could not write to xbox profile”. Then at the top right corner it continuously says “Equip failed”.

Is anyone else having this issue?

Edit: looks like its because I’m trying to set it to “X10”. Other values seem to work just fine. Am I getting caught in some weird filter? Why would this be offensive… Been using it since service tags were a thing…

I would potentially submit a bug report about this
https://aka.ms/HaloSupport