Purchasing a membership does not allow access to paid membership pages

Hello. I am in a panic here. My users are creating an account on my website, proceeding to PayPal to purchase the membership, and coming back to the website to access the membership pages, but they cannot access them!! Paying members are not placed in the paid subscription plan set up!!

I have the correct IPN URL in my PayPal account. I can confirm that my users are being charged, and that my PayPal account is accepting their payment, but the users cannot get to the membership pages on my site.

After a user creates an account, they are placed in a holding subscription that they stay in until they purchase a membership. Then once they purchase a membership through PayPal, they are moved into the paid subscription. This has always worked fine. Now after a user creates an account and is placed in the holding subscription, they stay in the holding subscription even after they buy a membership through PayPal!

And the thing that's most scary is that after I buy a membership and go back to the site, I have the option to buy it again and again and again. I am taking my customers money but not giving them anything for it!!

Can you please look into as soon as possible. I don't understand how this would happen.

Thank you.