If a customer cancels their payment plan and later needs to be resubscribed they can do this by just signing up again, entering new payment details and linking the new plan to their account.
Often it would be easier and a better experience for the client if the coach could do this process quickly and attach the previous or a new payment plan to a clients account.
This can done from the clients account page.
From the client list select the "Account" option (paper money icon).
Now you will see if there are cancelled subscriptions in the list, click the "Resubscribe" button.
Now you can choose the previous plan or a new plan to subscribe to the client to.
The plan will now be applied to the client and if their account had been disabled from the previous cancellation it will be re-enabled again.