BAD INTERNET CONNECTION

I've signed up for 10Mbp download and upload with Afrihost last month(May). All I have been getting is BAD INTERNET CONNECTION. I cannot make Teams calls, meaning I cannot join meetings from home yet colleagues that have 5Mbp with other ISP can connect with no issues. I now have to use my vodacom 3g wifi to make Teams calls if I have to join meetings. Like wow I have complained and I was told to reset my router and asked how many devices are connected. Like hello!!! only 3 devices is what takes your internet down??? I regret using Afrihost as my ISP.