Order to add a line keeps getting cancelled - chat no help

I have an account with 5 lines, and want to add a sixth line with a phone.  My order is completed online but keeps getting rejected.  The message is that they can't 'verify' me.   I've had this account for 10 years and pay over $3,000 per year to support these phones.  The chat folks say they don't have access to why my order can't be verified and completed and that I should visit a local retail location.  That is unacceptable, as I am at high risk with Covid, and am strictly isolating until vaccines are available.   I have a perfect payment record, and there is no reason I shouldn't be able to add a line and a phone to this account without going to a store.   If ATT offers online sales I should be able to complete the sale (or if they 'can't ' verify me, someone should tell me what extra information they need), but I've hit s dead end.   And all this over buying a $62 flip phone and new line for a senior citizen relative, on my own account.   I spent over an hour on Chat with them only repeating I had to go to a store, couldn't buy this online.   Very frustrated.   Makes me want to move all my lines somewhere else.   Where I can use the online facilities appropriately.