From the sounds of the question, it seems like you have tried many unconvincing ways to tell this person about your lack of personal mobile phone and I think if you’ve come this far, the answer is clear: there is no convincing someone you don’t have a cell phone. It’s 2018 for fuck’s sake, everybody has a cell phone. I was going to say that being old is the only reason you wouldn’t have one but my 80 year old grandpa, who I don’t think has ever touched a computer, has his own cell phone so that’s out the window!
The only explanation is that you just don’t want this “friend” to have your phone number and that’s okay. But the first step in solving your problem is to ask the right question in the first place so let me help. “How do I tell my ‘friend’ that I don’t like him and no longer wish to communicate with him?” Perfect. Simple and straight to the point without fucking lying about not having a cell phone.
So let’s move on to the real question. Just don’t respond to this person for the rest of your life. Any time they call, don’t answer. Any time they text, don’t respond. Any time they request to connect with you on social media, just hit ignore. Basically just pretend that this person doesn’t exist and eventually, they will go away. Human beings, for all of their flaws, can almost always pick up on people not wanting them around if it continues long enough. For some people, that’s a week, for other people that can be two years or even longer (we all know that guy).
There you have it, another internet member helped out. And remember kids, if you want your problems solved, you need to ask the right question. Nothing to be ashamed of if you don’t want to ever talk to a person again for the rest of your life. No cell phone, that’s adorable you rascal you.