The @ username is a tag. it alerts that user that someone mentioned them so they will see the post.
There is a recent post on the Hot Springs Moto-Massage that has some troubleshooting steps and links. For some reason I can't link the thread due to some site security rules.
The temp increase is probably due to heat from the pumps running. It's probably a bad heater relay, stuck open. You can check for voltage when the tub is calling for heat using a multimeter.
Relays are fairly inexpensive on Amazon and can be changed by anyone with electronic repair experience.