Square won't work with tap to pay on iPhone 12

This is a user to user forum, no one here is going to call you. It is a bad idea to post your personal phone number in a forum where millions of strangers can see it, I've asked the mods to remove it.

Contact Apple for support & service.

Contact Apple for support and service - Apple Support

or call

Canada/United States

1-800-275-2273

For other locations, look here -

Contact Apple for support and service – Apple Support (AU)

Perhaps something here will help:

https://squareup.com/help/us/en/article/5639-set-up-the-square-reader-for-contactless-and-chip

If not, you probably should contact Square's support for assistance.

Regards.

Are you wanting to accept tap to pay or pay with tap to pay?