My delivery and billing addresses are the same - not working

Step 1: Checkout Options - Register Account. When a checked Guest Checkout that bug did't found.
Step 2: My delivery and billing addresses are the same. - checkbox - checked or disabled
I got a redirect to Step 3: Delivery Details.

I fixed checkout catalog\view\theme\default\template\checkout\checkout.twig 243 line and bug fixed. I got redirect to Step 3: Delivery Details.

var shipping_address = $('#payment-address input[name=\'shipping_address\']:checked').prop('value');
Replaced
var shipping_address = $('#collapse-payment-address input[name=\'shipping_address\']:checked').prop('value');

But I have new error now: Warning: Shipping method required!
When I push a button Continue

Having the same issue since upgrade to 3.2.1. Shipping issues abound. First Region/State drop down didn't work. That miraculously started working after about 2 days of troubleshooting. But the shipping has been a nightmare! For new users, the shipping works okay - some issues. But for returning shoppers, that login to checkout, the DELIVERY METHOD is blank. No options. There is no way to calculate shipping and therefore, they cannot check out. Has anyone solved this issue yet?? Or is there a way to go back and undo the upgrade, this is very painful and losing money daily.