As it was explained, at the time of your stay there was a line fault coming into the building. This is a supplier issue. We, like everyone else, must wait for the supplier to send an engineer to rectify the problem.
So we provided a 4G router as an interim solution, with 12 GB of data, which cost us £60. The situation was clearly explained twice to two people in your family group and we did advise that if you were going to do heavy downloading that you would eat through the data quickly and it would run out.
The apartment is equipped with SKY satellite TV with children's channels, sports and movies.
To use up 12 GB of data in less than 2 days is enormous usage over the 4G (mobile data) network. It would take hours of continuous downloading to running out of credit.
Our interim wifi solution was generous; we are disappointed that your description of the "wifi not unlimited" is not an accurate reflection of the true situation.