Hi Fidgit,
I solved the issue.
Here is what you need to do :
Sign in to your braintree account and on left pane select plans.
Create a plan and enter a plan id.
Now in paid membership pro, Select the level which you want to activate that plan and give the previously generated planid from braintree in a plan id textbox provided there.
Save the changes and you will be able to do the transaction.
