Same issue with other carriers, I scheduled an appointment and hand it in for repair, they actually knew what's going on and replaced my motherboard on my S10. It's all fixed.
Your not alone mine is roaming unless I'm 5bmiles away from my house after that it's still hit and miss I pretty much have a nice camera and organizer when I'm at home tired of sprints runaround update did nothing either ugh
idk, so far its both, talk to samsung today, they are want me to go to the best buy store again, they said the one i ran to is not samsung, geek squad saying they are, literally WHO Is responsible with the phone?????, qeek squard did firmware update or software no idea what it is, of cuz did not work after 4hrs of waiting. samsung now saying go to samsung exp for them to firx it or whatever. but seriously if they going thru all that reset/restore ## blah blah blah, i gonna be really mad, cuz its waste of my time. i keep hearing sim slot issue, then motherboard issue, then software issue, what it is????some said replace phone it work, some said didnt , some said disable band works, which did for me but still having slow internet issue, but not NO internet issue. this is the worst exp switching from iphone to s10, wow samsung, u want ur phone beat apple, do the first thing they are good at CUSTOMER SERVICES and TECH SUPPORT.
done that, got worst, ##7 something, PRL updaate, software update(which claim thats what mess the phone up first place) restore, reset, firmware update, only thing seem to work kinda is band25 and 41 disable, but thats becuz those band is having issue, and 26 is working so far but gettting very slow LTE. kinda same thing like how the phone start having issue. and sprint doesnt know how to fix it, best buy doesnt know how to fix it, samsung is well dont think they know either, i think after all this research and what i went thru, the update came out a week and half ago cuz the phone issue, and i believe theres sometime hardware issue that they may already know about, and they are trying to patch it, but it fail, and made things worst, now they r trying to come up a way to fix it, some had replace motherboard and it is fix, some have replace the phone been fix, but some replace the phone didnt get fix. so this is where it at.