I have two ceiling fans and they both don't work. How do I find the code for the remotes that correspond to the fans to make them work. The fans are hampton bay fans model number uc7078t. Thank you

Receiver will be in switch housing or canopy at ceiling, to see what the fan codes are. You then match remotes to fan. You may want different codes for each fan.

I agree. Sometimes trial and error is the only way. But it's possible your fans have bad receivers, a power surge can cause this.

Ceiling fan remote controls - help and FAQ- Ceiling Fans N More

Also, if you don't want to go through removing, or disturb fan, go through the 16 combinations. Count binarily from 0 to 15.
0000, 0001, 0010, 0011, 0100, 0101, 0110, 0111, 1000, 1001, 1010, 1011, 1100, 1101, 1110, and 1111. These are the 16 combinations.
If they worked before, you probably don't need to change switches.
Sometimes removing power to fan for a couple of minutes will get it out of a "Confused" state.