Credit building up

I’ve made 4 payments so far since I’ve been with Bulb and the payments just seem to be building up, so I have over £300 worth of credit on my account. My usage is not showing, I see a message saying ‘We don’t have enough data to draw a graph yet’, even though I’ve had a smart meter for months and have not been asked to submit any readings. Is this correct?

No, it’s not correct. But this is a public forum for customers, it’s not a service desk. You need to contact Bulb directly by one of their private communication methods detailed in the Help section linked at the top.