2015 RAM 1500 - Bad fobs

Maintenance/Repairs
1

I have a 2015 Ram 1500 that I purchased new. My remote start stopped working 4 1/2 years after I got the truck. I thought no problem, I have the spare key fob that hasn’t been used at all and I will use it. It quit working about 2 weeks later. I thought no way. It must be something in the truck. I took it to my Ram dealership and spent $150 to have it checked out. They told me both fobs were bad. Charged me $340 for a new fob which did not include the key. If I wanted the key it would be an extra $40. My question is, how did the second fob go bad, even though it hadn’t been used? And yes I did put new batteries in both fobs. Everything on both fobs still work. Only the remote start doesn’t work.