PayPal Checkout Integration: Payment is stopping form Submit

payment is optional but not letting anyone past to click submit

then they try again and it says they already visited

It looks like the PayPal details are not correct in the PayPayl Checkout integration field.

If you would like to use the PayPal Checkout integration you will need to get a Client ID and a Client Secret from https://developer.paypal.com/. Please follow the next guide for more information:

How to integrate PayPal Checkout with your form

Then, update the details in your form.

Alternatively, you can use a PayPal standard integration where the Client ID and Client Secret are not required:

How to Integrate Form with Paypal (Standard)