Good advice to take screenshots, just done it for my igloo account, who keep insisting on increasing dds despite a £500 credit.
I had a nightmare approx 4 years ago when a small company went bust, had misread the meter and apparently owed me £1k refund, which I never got, then the next supplier thought I’d underpaid and hit me for £1k. It took a lot of phone calls to sort, and guess what my online account had disappeared so I had no access to evidence the meter readings I had given online. I am sure I’m hundreds out of pocket but gave up trying to get a refund….then a couple of years later I got a bailiffs notice saying I owed that company £150 and they were taking me to court, with no access to any data I just paid it so I could draw a line under it.
Now I take photos of meter readings every month in case I get stiffed again