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@Jürg191
I strongly suspect that Your host didn't pay the powerbill.
As You sayed the entire bulding does have electricity but only the apartment You are staying in has no electricity, that is very strange. This looks like the power supply company just cut off this one apartment.
A second indication is, that the power went down at 7am. Power companies always cut off electricity either in the morning or during daytime, they never do it in the middle of the night. First, their employees aren't working at nighttimes, and then it would be too dangerous to cut off power at midnight.
To get electricity back I believe Your host has to pay whats owed immediately. Promises will not be sufficiant. The host will have to go to a bank or to a postal office and pay whats owed in cash and then fax the receipt to the power company. I don't think there's another way.
I would bring all this up to airbnb, especially that this apartment is the only one in the building that is effected.
Of course I have no idea what the real reason for the problem is. But if it's the money and Your host just doesn't have the money, You may be without electricity till the end of Your stay.
Good luck.
