Facebook accounts

Hi folks.

I have a personal FB page, and my son wants to open his own page. We have one cellphone number to use. When he enters all the required info, he gets a pop-up that tells him the number he is using is already being used.

We don't much like phones, TV, radio, and such. There hasn't been a TV in the house since 1998...! We get daily news from a news agency on the Net, and the occasional newspaper. There is one cellphone for use by all members of the family (it stays home). My wife's Smartphone is government-issued for official use only.

Some of you have more than one account that uses the same number. When I go to "Ask the FB Community", I enter my question and come up with a "This link is broken" page, so I can't ask FB for a solution. I suppose he could open a business page but he wants to open a personal page.

Any of you know what I need to do?