Search by zip code returning 0 results

I have a search set up that users can type a zip code in and it displays the 3 closest results. I am using the address input field, but simply renamed it Zip Code so users only type their Zip Code. For certain Zip Codes (ex. 03256) if you just type the zip code and click search without selecting anything from the Address Auto Complete list, it returns 0 results. For other zip codes (ex. 17067) you can just type the zip code and press search without selecting an option from the auto complete list and it returns 3 results like it should.

Any suggestions why some zip codes work and other’s don’t?

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