I can’t send SMS and I can’t receive Verification codes if i sign in if i go to Name, Phone Numbers, and Emails. Help

My iPhone 6, OS 12 cant receive messages and i already tried going to my Apple ID on my settings and went to Name, Phone Numbers and Emails to input my phone number but everytime I do it asks for a Verifiction Code and I never received one. I tried going to Password & Security and went to Get Verification Code, it shows up but then when I use it for the Phone Number it always says “Old Verification Code, this code has expired” and when i keep trying it will say “too many codes sent” when infact i never received any codes. what to I do? Pls help me.




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