You seem to be determined to set the pedal up wrongly, which is why you keep having trouble. I don't see any evidence of faults in the pedal.
If you are using two amps, one for wet, one for dry, use Wet/Dry mode.
If you are using one amp, with an effect sometimes before the amp, and sometimes in an effects loop, use Pre/Post mode.
Obviously there are any number of more complex setups you can try, but those are beyond the scope of this forum.