Overheating error on phone not resolved

My phone keeps showing messages that it is overheating, then shuts down. My phone has been sent to the Vodacom repair centre 5 times now with no resolution. 1st time - Software update was done 2nd time - Another software update was done 3rd time - Phone was tested and showed no issues 4th time - Phone's motherboard was replaced 5th time - Software update was done My phone still has the same issue, I kept all screenshots and videos of the overheating messages that pop up, Vodacom did not even request the proof the 5th time. They keep confirming that they tested the phone every time and it shows that the phone works 100%. This has going on for months with no resolution.