Payment Not Working Properly For New Subsequent Subscription Plan

I have a 1-year membership setup. It works great.

Students are approaching the end of their first year, and I'd like to give them one of two options for continuing:
1. Monthly subscription
2. Yearly subscription

When I use one of my sample accounts and try to upgrade, it's confusing to the student as they have their active membership and then I'm asking them to sign up for a new one:

Question 1: Should I guide them to "Change" to the monthly? Or should I guide them to wait until their account expires, and then signup for one of the two options? Is there a better practice for this that I'm not aware of?

Question 2: When I click the "Change" button on the "Pro Ongoing - Monthly" option it takes me to the payment page (, and after I add my credit card it says it works (shows me a green checkmark) but it doesn't process my order:

I verified it didn't process my order on my account.

Any idea why it's not working?

I verified a new account signup still works just fine with payment.

Thank you in advance for your help!