Well, the way it works is the Stripe customer id is saved in the WordPress database and used for subsequent purchases. If the customer is deleted in Stripe, then the id in the WordPress database no longer references a valid customer and that will give you the “no such customer” error.
So, in that case what we could do currently is remove the reference in WordPress and start from scratch with a new Stripe customer. The problem being that in the current WordPress version of the plugin (1.24) I only added a button to delete test data site wide. In the github version, there are now buttons to delete test and live data per individual user (in the profile section). It’s experimental, but it might fix your issue for now.
In the future I’d like to add better error handling so if a customer doesn’t exist, it automatically creates a new one and deletes the old reference. That might happen for the next release, but I’m not making any promises.
Let me know if the github version works for you and adds those 2 buttons at the bottom of the profile page.