tub over flowing with water

have a Kenmore stackable water over flowing in tub. Water will not turn off. Dont have model number but do have part number to timer need to find out what model number is by part number.

Are you talking about units that can be stacked like the Kenmore Elite or one that the dryer is permanently mounted on top of the washer?

YES Its the stackables washer and dyer combo

Quick question; does the water continue to fill even when you turn off the system or does it stop when you turn off the washer? This will help determine if it is the water valve not closing or if it is the water level sensor. If the water does stop flowing when you push in the knob to turn off the machine then likely the water valves are ok.

yes water will turn off when power off

Alright we can then imagine that the water valves are good. [Oh by the way check inside the door of the dryer for the model# and serial #. The model number likely starts with a 417.****** and was manufactured for Sears by Frigidaire.]
Anyway the cause of your problem may be a faulty water pressure switch. It may also be a clog in the hose leading from the bottom of your outer wash tub up to the water pressure switch. I suppose you do not have any leaks??? If so the the hose may have broken or come loose from the bottom of the tub. If you’ve had a repair recently the hose may also have become pinched between the frame and the case.
The bottom line being the water pressure switch needs to sense a rise in pressure from the tube/hose that leads from the bottom of the tub or else it won’t know when to turn off the water.