Paypal's New Ipn (instant Payments Notifications)

This just started happening: I have a number of orders that payment is completed through PayPal (they are being charged) but the shopping carts are not being completed. We are not receiving the order and they are not getting an order # or email confirmation from us.
When I check on the PayPal transaction it shows queued only and does not update. PayPal said I need a notification URL, I could not find that information on the SYTIST menus. PayPal was no help their tech support kept telling me, to contact my Developer. Also I have received an email with new IP addresses being used for IPNs:
PayPal is expanding the Instant Payments Notification (IPN) infrastructure used to
notify merchants about events related to the status of PayPal transactions. This
change has added seven new IP addresses from which IPNs are being sent since
January 18, 2021. Below are all of the IP addresses that are being used for IPN.

66.211.170.66
173.0.81.1
173.0.81.0/24
173.0.81.33
173.0.81.65 (New)
173.0.81.140 (New)
64.4.240.0/21 (New)
64.4.248.0/22 (New)
66.211.168.0/22 (New)
173.0.80.0/20 (New)
91.243.72.0/23 (New)
My website person says they are not being blocked on our site. I am using SYTIST as my ecommerce/shopping cart add-on to our website. He said to check and make sure SYTIST program is up to date...how do I do this?
Any help would be greatly appreciated!

Edited by

Sytist sends the notification URL with the payment information (like it did for all the successful orders you had).

If you are using something like wordpress for your main site, maybe a plugin was added that is interfering.

Also see this: https://www.picturespro.com/sytist-manual/common-issues/customer-paid-by-paypal-but-no-order-created/

Edited by

Thank you!
I did check out the manual page you noted before writing...everything checked out okay. The orders I have issues with were not e-checks one was an AmEx and the others were debit cards from verified PayPal users. The result of the IPN status was Queued.
I have my website person checking on any new plug-ins. So far all the rest of the orders being placed have gone through.

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