"Error Please select a payment method for your order" no matter what payment method

I've got a ZC site that I just inherited as the developer the client was previously using was not able to fix the problems they're running into.

The problem that I am running into is that the only payment module I have enabled is Paypal express checkout, and it is enabled and configured correctly, but when I try to go through the checkout process, I can't get past the Payment Information screen, I just get an error "Error Please select a payment method for your order". I've tried enabling other payment processes, like check/money order, and when I have more than one, I get the radio buttons for selecting a payment type, but I get the same error no matter what payment method I select.

I've tried changing the PHP version back to 5.6, but that doesn't seem to affect the error in any way.

Template: Pure Green Free
Site URL: https://www.toadland.com
ZC Version: 1.5.6c
PHP version: 7.0.33
Database Engine: MySQL 5.6.41-84.1

Welcome to the forum. Tell the Horn Toad guy we said hello.

The forum search engine is not the greatest. We normally use Google with Zen Cart added on the end.

That said, you should also have some log files in your logs directory.

And, you might want to check out the similar threads below. If they're not helpful, post your log files here using the # to show the code.