Since you have a static code garage door opener, why not just upgrade to a rolling code remote unit?
Something like this.
https://www.homedepot.com/p/Genie-Universal-Garage-Door-Opener-Remote-Upgrade-Kit-Add-Modern-Intellicode-Security-To-Your-Old-Garage-Door-Opener-GIRUD-1T/100654121
Otherwise I would just try to reprogram the existing remotes and see if that fixes it.