Electricity price Power Meter Multiplier

I rented an airbnb and in the advertisement, the price was given as 7 baht per kWh. Now the host wants to charge 30x more because he argues that his meter spins 30x slower because of some technical reasons. He says, that this is a common thing in Thailand and multiplying the kWh figures with a factor is normal.

In my case the costs increase therefore by a factor of 30, so i wanted to know if this is a common thai fact that the metered kWh figure on the actual has to be mutliplied with 30 to calculate the real costs.