Why are my bills much higher than was "Estimated"

Having recently switched to Bulb in November 2018, I now find myself in a position where the original “Estimate” is almost 50% below the actual. I live in a 3 bedroom mid terrace house and I suspect fall bang in the middle of Bulb’s customer demographic so how could Bulb get it so wrong! When I complained I was being asked on the system to raise my payments by almost 100% of the Original “Estimate” I was told the system was wrong and I only had to raise it by 30%. Even 30% is an astonishing failure in the original estimation. Is it an error in estimation or is it dodgy sales tactics?

Did you submit actual usage figures when requesting a quote/signing up?

Bulb’s estimates are only as good as the information you give them to work with.