What do you do when one half the jets are working in a Mirolin massage tub

Fill the tub until the jets are covered by 2-3 inches of hot water. Add 2 Tablespoons of a low-suds liquid dish wash soap and 1/2 cup of white vinegar. Run the tub with the solution to clean the jets. You can also use bleach instead of vinegar.

No I posted an answer on your other post

No they do not here is a simple way to clean the jets and the piping.

Regular Jet Cleaning

To clean the entire whirlpool system and tub exterior, follow this process every month or more frequently if needed. Don't let dirt and grime build up or you'll have more scrubbing to do to get the tub clean.

1. Fill the tub with hot water, approximately an inch above the highest jet.
2. Make sure the water temperature reaches at least 140? F (60? C).
3. Add 1/2 cup of laundry detergent or the amount used to clean 1 load of laundry as recommended by the detergent manufacturer.
4. Run the jets for 15 minutes.
5. Drain the tub and refill with clean lukewarm water.
6. Run the jets for another 15 minutes.
7. Drain the bathtub.
8. Dry the tub completely by wiping it down with a clean towel.

Almost all hot tubs use 230 volt AC power which comes from the power company in two power wires plus one common common wire. You get common 115 volts between a common and either other wire. "Half way" working could well be an attempt to run on only one of the wires. There is also likely to be a ground fault circuit breaker in the wiring which makes sure current going out to the tub is all returned via the wires and not through someone's legs to ground. If you're comfortable with an AC voltmeter check some voltages but understand that 230 volts is way into the killing range. Two people present and well insulated probes are important.

Air Switch Repair
It sounds like you have a bad air switch located in your motor.
The air switch is what the air hose connects to on the back of the motor or on the box on top of the motor. The other end of the air hose is connected to the air button on the lip of the tub.
This is a latching air switch and when you push the air button it latches to send power to the motor. When the air button is pushed again it opens the latch in the air switch and stops power going to the motor shutting it off.

US Parts Center

If your pump will not shut off then the Air Switch in the motor is most likely the problem with the pump not turning on.

Rod
US Parts Center

Mirolin warranty is horrible. Immediately after install the tub leaked because of a defect in the tub's drain hole. Mirolin won't cover any damages caused. Had to pull our whole ceiling below and replace flooring.

There are several cleaning methods on the internet. I would contact the maker of the tub and see if they have a cleaning agent. I know that Jacuzzi and Aquatic industries have a cleaner that works rather well. I have seen one on the net that uses 2 teaspoons of powder dishwasher soap mixed with bleach. I have not tried this one so don't know how well it works. The ones from the tub companies are not cheap, but if you want something that is going to do the job, spend the money.