Keyless fob stopped working

Anyone familiar with possible solutions? My 2012 Toyota keyless fob suddenly stopped working. Not a starter, just a door lock fob. Checked what fuse I think is related (under dash 20amp). Changed the fob's battery.
Anyone, anything else?

Edit: FIXED! Thanks again TW. Someone posted a link which I'd saved on reprogramming my fob.

 

I bought a 2 pack from Walmart on-line (supposedly OE) that look exactly the same, for about $16m got them about 3 says later, followed the steps to sync to truck, and after about 3 tries, was good to go.

 

Good to know. Need a spare.

 

My 3 (2 brand new)- aftermarket fobs stopped working out of the blue too. After checking for good batteries reprogramming worked on the 2 new ones. I had not heard of fobs just "un-programming" before. Great info programming here:

https://www.tacomaworld.com/threads/key-fob-keyless-entry-remote.678741/#post-23896630

 

The contacts wore out on mine. I opened it up and put little squares of foil between the contacts and buttons, and they worked great again for a short time, though the foil was hard to secure, and they needed to be repositioned occasionally. That finally became a pain in the ass, and then went the route described above....