Not sure this is a fix but I recently delt with FOB issues with my 2019 Silverado. My battery was definitely in need of replacement after 5 years of use. The FOB would still work but had to be right next to the truck to open doors. I took the FOB apart and replaced the battery and now it quit working all together!! After taking it back apart several times I finally noticed that the silicone insert was not completely seated. There are 5 little plastic knubs that have to be seated on the silicone insert. I saw that one of my knubs was not seated perfectly. Once I corrected this it worked fine. Just another possible fix, I hope you're as lucky as I was!!!!
