Basically i just bought this home and the thermostat is set…

Just respond here when complete.

I'm with some other clients but it will alert me when you responds , and i'll be right with you. Thanks

does the indoor fan go off when you switch fan to auto, it may take a few min after you switch it to auto

You'll need to turn cool to off and fan to auto then see if indoor fan shuts off.

Ok turn AC to on turn temp down and push hold  and leave fan on auto, wait 7-10 min and go outside and let me know if the outdoor unit is blowing and see if air coming out feel hot warm or average

yes put on cool and fan to auto,then wait 7-10 minutes then go outside

Thanks

ok let it run a little and see if it gets warmer

Yes the outdoor and indoor too.

Then after a few min  go inside feel to see if the air feels cool now as well.

if the thermostat continues changing by itself, it may be bad or the programming is just memeorized and wont reset unless the internal lithium battery dies. If the unit is cooling now i recommend just replacing the thermostat with a new one so you can program it to your personal settings. If the unit isn't cooling then your going to need a onsite tech to trace out the problem.

Is the air coming out inside feel cool now or still room temp?

ok , i believe you have a few problems, one being the thermostat, but it sounds like something isn't working on the equipment side, if the unit indoor and outdoor are both coming on, this means the thermostat is actually working and telling them to come on, but as far as the thermostat changing by itself means that part of the thermostat is bad or cant be changed. at this point you need a field tech to come trace out the problem or problems. I'm sorry it wasn't something easy but i believe your have a couple of issues and would be hard to find by chatting. The thermostat isnt the reason the unit isnt cooling there is something else not working, but like i said you still may need to change the thermostat because of the changing back by itself, but its actually bring on the equipment but theres something wrong with the AC part of the system.

Can you tell if the compressor is running outside with the outdoor fan?

while its on outside touch the big copper line that connectes to the unit and see if it feels cool or is sweating with moisture.

Its the one with the black insulation wrapped around it

ok , if the compressor is running(the black motor in the bottom of the unit) and this line isn't cool or sweating, this usually means it low on freon and if it is low that means there is a leak somewhere in the system. This leak could be outside or inside. You need someone to put gauges on the system to check the pressures and see if it is low on freon. Did the unit ever cool after you bought it?

Ok , they may have charged the system right before the sale and it has now leaked back out, I'm not saying that is for sure but have seen it happen many many times in home sells. They charge it up during the selling process and it passes inspection then a while later the freon leaks back out and you then have to deal with the leak, like i said not saying this is what happened but ive seen it many times.

i understand but if all the equipment is coming on the thermostat is doing its job, as far as removing the setting, that shouldn't have any impact on the unit not cooling , if the equipment is coming on it is getting its signal from the thermostat to come on. The setting can only be removed by doing a factory reset, and we tried that by placing the batteries in backward and then placing them back in correctly, this didn't reset it so it probably has an internal battery that memorizes the program. if you were to put a brand new thermostat on, and everything you've told me is working and is in fact working, then the new thermostat may remove the old setting but the equipment still will have the problem. If everything is running like you said it was today, all the thermostat does is tell all the equipment when to come on, and it is doing that but still isn't cooling, that's what i meant when i said you have 2 separate problems. One the thermostat has to be reprogramed or replaced and 2 the equipment isnt working right after the thermostat tells it to come on.