Mine did the exact same thing and the battery needed a full charging that the tender was not giving it enough of a boost to start the bike. It’s a very common problem when the seasons change and get colder.
How old is the battery? Have it load tested for a dead cell. What electrical system is in the bike? Sounds like you have electrical issues in the wiring.
Maybe check the starter and or run button for an open/closed circuit? With the key in the on position, the starter shouldn't engage unless the run button and then start button are pressed in sequence.