Yamaha 90 outboard beeping alarm when going full throttle for more than 20 seconds

Hi - I have a Yam 2000yr 90hp 2 stroke outboard and anytime I am going full throttle (really not even full, more like 3/4) the alarm starts going off. It takes about 5 minutes of turning the boat off for it to finally go off. I feel like there is just something tripping it maybe? Because it never goes off if just trolling/cruising, it is the same scenario every time of going faster. There should be no reason I can't go fast for less than 20 seconds at a time. I use oil mix since its a 2 stroke. Is this maybe a bad t-stat? I have no clue so any help would be appreciated. Thank you.

Do you have a yamaha tach gauge? If so, the gauge has visual alerts for low oil and high temp. Look at gauge. If you don't have gauge then it's a guessing game. Easiest to to first rule out is oil....verify main tank is full. If it is then safe to assume it's the high temp alarm. Question is, is the alarm tripping because of overheating or because of bad thermosensor. Test sensors.