I don’t think I’ve ever had this issue. Here’s the full method.
Put teabag and spoonful of sugar into mug, pour maybe 2cm of water into mug. Nuke for about a minute. Let sit for a bit. Agitate the teabag a bit to get more of the delicious leaf juice out. Chuck out the tea bag. Pour in milk. Nuke for 20 secs. Done.