Chances are the interior of the potato was not fully cooked. That’s why we recommend peeling and cutting the potato into even sized chunks, 1 ½ to 2 inch cubes and then boiling. For a drier mashed I’ve had success in baking potatoes with the skin on till 210 degrees F inside, 185 degrees minimum. Then using oven mitts,slice the cooked potato in half vertically, scoop out the insides and mash, turns out extra fluffy as the oven baking has removed a lot of the moisture.
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