Unable to change call forwarding number Samsung s21fe

Subject line pretty much explains my issue. First off all, there is a different phone number listed on my call forwarding options, and I keep receiving an error message each time I try to add my number into the always forward option. Not a single troubleshooting step is doing anything aside from (Edited per community guidelines) me off! Not a single tech has done anything aside from sending me into a circle (Edited per community guidelines)! Is there anybody on this planet who is actually willing to just be straight right from the start? Samsung galaxy s21fe post paid unlimited new account ported phone number brand new cellphone. Need more information? Just ask! Be straight or just move on, I'm sick of circles and want a solution since I am missing important calls intermittently,