The door latch won't close. The light stays on. Display kept saying close the door.

Repaired latch inside door, but when I close the door the light stays on and reads close door
How To Fix A Stuck Latch If your door can open correctly but can't close without getting stuck, it's likely an issue with the latch. Multiple issues can compromise door latches, such as a mechanical error, worn down latch components, broken door handle cables, and more. If the latch is simply stuck, you should be able to fix this yourself without taking your car to a mechanic. Just take some oil lubricant, like WD-40, and spread/spray it into the latch mechanism of your open door. Let the oil soak in for a little bit, then use a microfiber cloth to rub the oil into any visible parts of the latch. While performing this task, check to see if you can find any rust on latch components. If you do, use a piece of steel wool to scrape the rust away. Once removed, try opening the latch with your door handle to confirm that it is once again functioning correctly. In some situations, your latch may accidentally be closed when it should be open. This can happen for multiple reasons - sometimes due to an electrical glitch or a mistake made while repairing the door. Either way, if you have a car door with a closed latch, try opening your door and looking at the latch to determine its orientation. Then, open a functional door and look at the latch to see how it's supposed to be. A working door will have a latch with "open" jaws. These jaws can catch the door jamb anchor and rotate into a closed orientation to secure the door. If the latch's jaws are already closed, it can't engage with the anchor or close properly. To fix this issue, take a screwdriver and hold the door handle in the open position (pulling if necessary). As you pull the handle, rotate the latch with your screwdriver into the correct orientation. If needed, ask a friend or family member to help you hold the door or hold the handle open for you while you perform this action. Once you have moved the latch into the correct orientation, test the door handle a few times. The latch should open when you pull the door handle, and the door should again be functioning correctly.

Try this link ... owners manual ... go to page 15

https://www.searspartsdirect.com/partsdirect/user-manuals/gsc309pvs02-whirlpool-parts-manual

It shows how to remove the door and talks about how to release the latches.
It sounds like whomever cleaned it ... may have removed the door and not reinstalled it correctly??
Helpful?

There will be a simple switch fitted somewhere on the door latch mechanism. This has broken so the door is not registering as open or closed.

Door and/or latch assembly is out of adjustment. Some can be adjusted internally. After making any repairs on a door or latch, the oven needs to have a leakage test done.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/david_29ad5d1dd86564b0

If the light stayed on AND the tray kept spinning around, or a fan kept running, then I would say you have a bad door switch. But if everything else works like it is supposed to, then you probably have a relay on the main control board that is stuck closed (on) or you have a shorted triac on the main board. Since very few technicians troubleshoot down to the component level or repair boards, you are probably looking at a board replacement - a rather expensive proposition to fix a light that is stuck on.

If you need further help, reach me via phone at https://www.6ya.com/expert/ronald_e6b9572cebe3ad27

Door Latch might be defective.

Check latch assembly and look for broken spring.

If it has the "double hook" type latch on the door,see if the hooks slide up and down.They should be spring loaded,if not,the spring attachment point inside the door may have broken off(my Sharp Carousel did this).I pryed the plastic door trim loose,and reattached the spring by using one of the slots inside to hold a metal wire clip(modified with needle-nose pliers) to hook the spring onto.Your door's design may be a little different,but a similar solution will probably be apparent after you get in there.

see this causes and fix it. God bless you
Open Lever If the microwave door won't open the open lever might be broken. This part can be replaced separately.

Door Spring If the microwave door won't open the door spring may have broken. The door spring is located inside the door and keeps downward pressure on the door hook.

Door Latch If the microwave door won't open the door latch might be broken. The door latch is inside the microwave. The door hook, which is part of the door, engages with the latch to keep the door closed during operation. If the door latch or actuator breaks the door may not open.

Door Hook If the microwave door won't open the door hook might not be releasing properly. The door hook is installed inside the door and normally releases when the door is opened. The hook is made of plastic and will break over time. When this happens it will need to be replaced, it can't be repaired.

Button Spring If the microwave door won't open the button spring might be broken internally. The button spring can be replaced.
Button If the microwave door won't open the button might be broken internally. The button can be replaced.

Handle Actuator If the microwave door won't open the handle actuator might be broken. This is a plastic part which can become brittle over time. This part is connected between the door button and the door latch assembly.

the door switch needs adjusting recommend a service tech to do this