Apple Pay zip code mismatch though address shows correct

75% of the time, when trying to use my Apple Cash at a gas station (the only place I use it), I get an error that says Zip Code Mismatch, though I am putting in my home address's zip.

It is not tied to a credit card, I am using my apple balance (which more than covers my purchase).

The other 25% of the time, it goes through without issue.

I have checked my address on my phone, I am typing it in exactly as it appears on my address (and have verified that it is correct).

I have used at machines that show the numeric entry of the zip code, so I know the right numbers are being entered.

I just can't figure this one out!