You are in tricky territory when it comes to TK LEV and other TK products. There home elevator, accessibility division shut down about 3 years ago so getting parts and support is very difficult.

E2 is a result of a critical fault in the selector system and can be triggered from a ton of things (door zone sensors, normal limits, out of alignment of magnets, etc).

If you are not under contract for this I would tread carefully, you may end up in a quagmire and own something you can't get out of. We've been retrofitting LEV installation over to Savaria Eclipse drive systems when major parts and boards have failed, while not the cheapest answer it makes sense in the long run to have a supported product. It becomes almost dollar for dollar in cost when the drive unit goes bad.

My suggestion would be to check the leveling magnets, see if any fell off or are moved around. They could have also just become demagnetized to the point of not being picked up. If you look at the service history, more than not this happened when the elevator got to a particular landing and sat for a while or right after getting to a landing, typically the same one.

The leveling magnets get read by the selector to tell the controller how close the car is to the landing as it is approaching and making it stop at a sweet spot where it needs to be to be level with the sill. If they are not reading correct or have shifted it may make the car stop beyond the landing just enough to go past a normal limit, so while the selector is reading the lift has stopped physically where it supposed to be, the normal zone limit switches may not be activated do to the shift, confusing the controller. The selector is telling the controller the lift is where it supposed to be but the limit switch is not active so its seeing conflicting information.

Check the magnets are straight, they are set in a pattern indicating the landing stop, you may have to contact TK Access parts for an installation manual if one is not on site. Check the car top and the pit to see if any fell off.

If it is not the selector or the magnets another common reason for this was the DZ1 and/or DZ2 relays have gone bad. You can exchange them for the ones for the brake and see if that stops the issue. If you have ever seen a C2 error, those are also related to the DZ relay's going bad.

Resetting the UPS is not enough to diagnose the issue, upon resetting it the elevator cycles and homes (unless a door or gate contact is open). My guess is its the relays.

Hope this helps. Be safe.