Stranger is actively using the number associated with phone line for my home internet.

My home internet device gets spammed daily with texts of recent activity, current lyft rides, personal sms from someone named Keith. They have multiple online accounts linked with the number. I see daily lyft ride sms sent to him and 2fa codes for virtually every type of account this person has whenever he tries to login anywhere. It goes as far as even showing his government login links with verification codes for this person. I texted my home internet number from my mobile phone line requesting anyone who receives this message to cease use of this number immediately. To which I received a response text. Just stating "I'm scared". Even more concerning is how they are still actively receiving any texts that go to my home internet's line. Let alone reply to a text I sent from my mobile phone to the line. This is a serious security issue for me. My business runs on my tmobile home internet. I don't want potentially bad actors to be able to read my own SMS verifications in the future if I were to make an online account using the line. Let alone having my business internet spammed with someone else's personal data and information. This puts me in a situation where I cannot use the phone line number myself to set up online accounts like for example Lyft. I assume because it is a reused number that the previous owner of the number has it linked to many online accounts. And simply just hasn't or is refusing to remove the number's associations with his accounts. When my box gets spammed with these texts it will slow down the device and sometimes cause a hard crash causing me to forcefully reset the device. This person is still having correspondence with unknown people through my number which I've received their intimidating sms back and forths on my home internet device. There are services like google voice where someone can input a real phone number to receive a virtual one where texts and calls can be forwarded, managed, and sent from. I can only suspect the previous owner of the number has attached the line's number to one of these services in the past and is still actively interacting with the line that way to read them. Just deleting these texts isn't enough. This changes the performance of the device and makes it a security risk. There is still no option from t-mobile on the website to block sms for the device entirely. On the online portal selecting the home internet line in block settings just gives you this warning. "This line does not include these settings."