I have an older Qolsys remote keypad that spontaneously goes offline and loses connection to the main panel. When this happens, the remote panel is off but can be restarted by pressing and holding the side button until the unit restarts. During the reboot sequence I can see that the battery is fully charged. I already tried updating the software; it seems to be on the latest version. By the way, the error message I get from Alarm dot com is “The keypad is offline as of …”
This keypad is going offline almost daily at this point.
Can you try unplugging the keypad and just let it run off battery? Let it run that way until the battery is drained completely, then plug in and let charge.