Has anyone had any success with the QueQ app for reserving an appointment at immigration?

When I try to confirm, all I get is "outside the location or not yet scheduled".

I test that app quite awhile ago, sent them some suggestions to improve it and then tried it again a couple months ago and it was working fine (except that if you made an appointment you couldn't cancel it).

Make sure you have Location Sharing enabled. The app looks for the closest Immigration office to you. Before Jomtien went "live", the app kept trying to direct me to an office in Phuket ! (I had location sharing on, but Jomtien hadn't yet "joined" the app, or hadn't set up the software on their end.)
Once they got things done, suddenly the app was defaulting to the Jomtien office as it is designed to do.

Last time I was at Jomtien (6 weeks ago or so), just before they opened the doors to the general riff-raff, the PA voice started calling out some weird numbers. Those were appointment numbers for people who'd scheduled their appointments (for whichever desk) to be at the start of the day.
After they waited a few minutes for the appointees to show up (or not) then they started letting the riff-raff in.

Tried again this morning to make reservation for Wednesday. Still not working, thought they may have sorted it out following the weekend.

Maybe the message "not yet scheduled" means the system is not working or the person who operates it is not working ????

I'm on the app now and it's letting me make an appointment for Wednesday without any issues. I don't want to complete the appointment procedure as I don't think I can cancel it afterwards and I don't want to mess things up in case one day I actually need to make an appointment. (Not that they may record phone numbers and cross reference missed appointments or anything.)

Are you in/close to Pattaya ? When I open the app it gives me the choice of Pattaya or Samut Prakan even though I'm in Pattaya. I'm 11 kms from the Pattaya office and almost 150 from the Samut Prakan office. Not sure why it's even showing up on the app.

The only other thing I can think to do would be to uninstall the app and then re-install it as maybe somewhere along the line a "permission" wasn't allowed and therefore the app isn't being allowed to connect to the Immigration system.