How do I change conia air conditioner CA30003 from cooling to heating

call for HVAC service in town,
or ask maker for support in your unstated country.
must I guess this, is it Australia? if yes google 1st hit is here

wild guess #1 down under and Shrimp on the BBQ.
Conia A/C

https://jaricgroup.com.au/air-conditioning/brands/conia-air-conditioner-service-repair/

has it been wired correctly for that action

Sounds like either bad reversing valve or to get you going during the summer someone may have wired it to stay energized all the time which would have been a thermostat problem.

if it is set up for it

no heat on/off button on ours
we increase the the temp setting till warm air flows

homeappliance.manualsonline.com/ex/.../conia/.../air_conditioner/.../ca2...

it is necesary to work all the unit in same mode ,cool or heat ,or something too

Conia CPA 12020 immaculate cond, but the bottom motor compressor won't go on and cool. Just top fan. Anyone know what could be?

It's likely low on refrigerant and freezing...turn it off, coil thaws , cools for a short time and freezes up again. Chances are the leak or leaks are at the flares where the copper connects to the unit. Need leaks repaired and systems recharged.

If you need further help, reach me via phone at https://www.6ya.com/expert/thomas_092728000e6acb79

If you feel cool air near blower, you have to service your unit completely. Because it's giving cool but not removing heat from room due to coil and air filter blocking. Helpful?

there should be a mode button, press it until you see the sun sign