Units I have programmed tend to feeze about once a month. SO when I hand off to the customer I often start with... "Electronic devices pretty much always have a reset on them... here is this one's. Remove the back panel like this. Please just hold it flat in one hand and slide it... do not get a tool and pry it open. Pop a paper clip where it says reset. You will hear two beeps and the remote returns to when I walked out the door. IT DOES NOT ERASE THE PROGRAM."

Something like 90% of the calls after the fact are cured with...did you reset the remote yet?
bee beep
"Hey its fixed now."
Just remember the reset trick and you will be back in business right away... no need to wait to call me the next day.
"Thank You!"