2008 90hp Mercury EFI outboard engine stall with beeps

hey everyone, im not a handy man can anyone help me understand what is going on...i pay for my boat to get professionally worked on/maintainedevery year to prevent problems, and i bought the motor brand new for the same reason. i was anchored up all day relaxing. at the end of the day, i started heading back to the dock. i was crusing at top speed like i always do. without warning and for no reason, i heard a series of "beeps" (the sound it makes when i turn the key at every start) and then i lost speed/power and the engine stalled. i think it was a total of 4 or 5 beeps. i was able to start it back up but i was clearly getting maybe 1/3 of my engine speed/power. it stalled 2 more times with no beeps, then another time with the 4 or 5 beeps agian but i finally made it back to the dock. it gets serviced in the fall/spring, has a water fuel seporator which i check and drain regularly if needed, i only use gas on land cause i had an issue once with bad gas from a marina and water in it... why is this happening??? any idea? thank you!