Unable to downgrade from Professional Plan to Individual Plan

Hi, I opened a seller account over the weekend and I want to downgrade from Professional to Individual plan but the buttons are all greyed out with a message saying “You have another service associated with this account which does not allow you to change your subscription status”.

I’ll try and post a screenshot link in the comments.
I also want to unenroll from Fulfillment by Amazon and Selling Subscriptions on Amazon (buttons are greyed out too) and I couldn’t figure out how.
Any ideas?