Vumatel slow fiber speed

I signed up with supersonic on 16 September 2019 and was happy for about a month with no problems ...sins October I complained so many times have all WhatsApp messages phone calls and emails send with recorded videos about my fiber 100Mb down and 100Mb ul . Problem is during the day there are no issues and just after 6 every day I het speed drop from 100Mb to 7mb during night time and this is going on now for almost 2 months without vumatel coming out.. supersonic thecnitions was at my property and they said that this problem is coming from vumatel . Now I am at that point where compalints ain't working as nothing is being done on this subject . Paying for service this poor is absolutely a disgrace. Vuma or supersonic sort this **** out cause 2 months of complaints and no progress Wow I thought telkom was bad ..