I’m no expert and unable to find this topic. My cousin is 600 miles away and got her 600 into service search. How do you get out of Service / Limit search and return to regular scan of the programmed items.
I have one of these scanners on my desk and simply pressing SCAN takes the scanner out of any type of search back into scan mode.
Strange... Maybe try having them press MAN and then SCAN to see what happens.
It is possible the SCAN button has stopped working.
These scanners are notorious for the contact material flaking/falling off the back of the button that makes contact with the circuit board. An E-bay seller sells some "keypad fix" glue (metal/rubber mixture) if this is the problem and someone knows how to open and get to the button.
There is a small possibility they unintentionally turned on a scan list (bank) that has a service search or limit search programmed into that scan list (bank). This scanner allows searches to be part of a scan. They may have to turn off a scan list that was enabled unintentionally. Just another possibility...