Account credit

Hello,
I’ve switched my energy providers two weeks ago and my bulb account displays the message that “your account is currently being closed”, however my direct debit still came out today despite this and I’ve already started paying the new provider so I’m being double charged. When will the credit from my account be returned?
Thanks

This page and links from the page may answer your question: https://help.bulb.co.uk/hc/en-us/sections/115000338032-Previous-supplier-Exit-fees

The pages relate to what happens when you move to Bulb but it is still applicable if you move from Bulb (in this case old supplier would mean Bulb)