Recent software update issues

[userxXT4VaCSLx]

Hi I updated my software on October 21st and since then I have been getting a warning every time I restart my phone!! I have the s20 ultra 5g with t-mobile. I've been troubleshooting with two t-mobile but the problem isn't getting fixed!! 

[DGM]

what is the warning message you are getting? you can always call Samsung support at 800-samsung. however, the T-Mobile techs are probably better than the Samsung techs.

[userxXT4VaCSLx]

security error: this phone has been flashed with unauthorized software and is locked

[userxXT4VaCSLx]

I have no idea where there is a Samsung store near me lol. I know where t-mobile is thats my carrier

[Samsung_Q7nlI2E]

what's the version? it's in the About phone -> Software info -> Build number