Sometimes, internet problem, other time vacations, then office being burnt and now finding new office and promising me to pay this week
I want to have opinion regarding are these genuine excuses? Is there any relation of settling down and settling invoices? If yes, then he promised to pay this week but again he is not responding.
They are simple excuses since it seems that they A) do not have the money to pay you; B) have the money but won't pay you until their customer pays them; or C) they will not pay altogether.
In any of the three cases, the situation reveals that this is not a reliable business partner. Wait a couple of weeks more, trying to be as much a pain in the neck as possible (invest in calling them over the phone and making them lose as much time as possible), and if the situation is not resolved, add a bad mark for them in the Blueboard, so that others do not fall in the same trap.