Smart Hose Timer - No Flow Detection

I received an error code saying no flow detected on unit 1, make sure the faucet is turned on.

The second timer, unit 2, connected to the same faucet, ran flawlessly.

I tried to run unit 1 on the quick run cycle. It would start and then stop, giving me the same error - no flow detected.

It has been 3 hours, and I have tried again. Unit 1 ran for the time set but still gave the error that no flow was detected.

What is the fix for this error?