SMETS 2 and monthly bill

I have a SMETS 2 installation, my IHD is now working and my energy use is getting sent to BULB. So why haven’t Bulb produced a bill since smart meter installation? My monthly payments are way too high for the energy I’m using. Yes I understand the idea that one is in credit during the summer months to help with the winter. However, I was only £20 in deficit at the end of the winter period and without a proper invoice I’m set make Bulb a massive interest free loan over and above what is reasonable. It would seem the benefit of smart is only one way.