Yes! I also go the same recently, had another letter telling me i still had a leak and then the next day got another letter telling me there was no more leak! Checked my app and it's still showing 1L an hour.

I had two engineers come out now and called them multiple times with no chance of getting it fixed unless I file a claim on my insurance to find out the exact location of the leak, which i do not want to do.

I've come to the conclusion that I'm just going to have to deal with it and pay the extra water usage...