Have phone, Have Plan, need smaller SIM card. Site is stupid

What I need is a Nano SIM card for my new phone while my old phone (that's literally falling apart) has a larger SIM. How am I supposed to simply buy a SIM online when your site stubbornly forces the free SIM promo that requires a new plan/device to be purchased? I'm not settign up a new plan, nor am I willing to pay $80 for just a new SIM when my existing plan renewed literally 2 days ago.

You closed all the physical stores near me, so that's not an option (otherwise I would have already done so). Live Chat on the Contact Us page is swamped at all hours of the day. Between getting stuck for 6 hours on hold then having to go to work through the rest of your operating hours I cant talk to anyone over the phone.

I LITERALLY JUST NEED AN AT&T PREPAID SIM CARD KIT. I WILL PAY THE $4.99. WHY DO YOU HAVE TO MAKE THIS IMPOSSIBLE?