You may want to check Your power supply going to the router! I usually find that if I lose power to My tools that something I plugged into (power cord, Circuit Breaker) is generally is the problem. You don't mention the age of the router, but other possibilities are' dirt in switch, the brushes, damaged power cord on router. If You have done a lot of routing with the router in an upright position, dirt can stand in pockets in the tool, and when set upside down in the table, vibration can loosen dust and dirt. Just some things to check!
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