Since its just a short distance, we decided to go there in the afternoon. And by the time we reached the place, we discovered the reason why their phone line is not working. If you look at the picture below, this is the normal way of laying the cables in the ground. There would be a few outlets in the ground and with only a metal plate. However, because these are small plates, no one has ever bothered about making a proper hole for the cables to go through.
Therefore, it is not uncommon to see square holes being cut like the picture below. Unfortunately, because the holes cannot be adjusted at whim, they will be there permanently. It is too expensive to break the tiles, hack the ground and cement them again, just to move it a few centimetres or so. Some contractors would lay additional PVC casing for the cables as aded protection.
The reason why this is so critical is that the metal at the opening serves as sharp blades. When the customer's roller chair or shoes kicked into them, it cuts the cable bit by bit until the wires are exposed. By then, it will either create a short or, gets cut further. So, the only solution we could do was to rejoin the cable and tidy it up. We also requested the customer to use a small cupboard to "cover" the exposed cables so that the chair does not knock into it.