Moving date in new flat

good evening,

we will move in the new flat the 1st December but when I did the join with you, the date on activation will be the 18th December, there will be a possibility too have the light and gas the 1st December??

When you move in, there will already be a company supplying the property. The previous owners, tenants, or agency should be able to tell you who this is. You’ll need to contact them to arrange payment as a new customer to cover the period from 1st December to 18th December.

You shouldn’t really have started a supplier switch yet until you have legal responsibility for the property, which I presume happens on 1st December. You may find that the switch to Bulb is blocked by the current owners/tenants.