Pathetic ISP. Over 12 days without internet and no feedback.

This is my 3rd review as my problem is not getting solved at all. 10 days ago i was told my router is faulty and that supersonic will contact me for delivery of a new router ref nu:WO230759, I missed one call while being in a meeting, nobody phones back, I went out bought a new router out of my own pocket at connected it with the fibre router MYSELF!! My internet is crazy slow. I was without internet for 12 days!! I work from home and lost 12 days of income and are on the verge of losing my job due to BAD INTERNET!! This so so unacceptable if someone from you office do not contact me today I will take this further. Enough is enough. I have had it with begging and pleading just to get what I pay for everymonth and then still I need to buy data and stuff out of my pocket just to keep my job.