Paying 10mps only get 2mps

We signed up with telkom last year for a new business,to this date we have not received a technician to sought out line issues and internet issues,we then went over to mweb who activated a 10mg line we then did a speed test to find telkom had cut out line to 4 mps keep in mind we paying for a 10mps line and gave no permission to downgrade our line then they blame mweb and mweb blame telkom we not sitting in the middle paying for a 10mg line from telkom and mweb and only getting a 2 mg line when i contact them their response is they will investigate, i suggest all business and home owners run a speed test to make sure what you paying for is legit as this is pure theft and against the contract that one signs for.****** *****s.