Offline Payment for Subscription

Hello friends,

I have a website where we sell a discount card for individuals to have discount on our listed hospitals and pharmacies,

We sell the card using Woocommerce and yith subscription, when the customer by the card after filling the checkout form they don’t get the thank you page instead they receive some kind of an error massage, and there order is being place in the orders page and the is display pending payment.

I don’t have any online payment yet i am only using cash on delivery and some costume payment that i made which is popular in my country, but both are offline, maybe yith subscription don’t accept offline payment which cause this problem.

can you guys please help.
Thank you.

The page I need help with: [log in to see the link]