"used to" alone is correct in many situations, "didn't used to" is considered wrong by prescriptivists. Including the "didn't" in the search shows that it's st

"used to" alone is correct in many situations, "didn't used to" is considered wrong by prescriptivists. Including the "didn't" in the search shows that it's still close though: https://trends.google.com/trends/explore?date=all&geo=US&q=didn%27t%20used%20to,didn%27t%20use%20to https://trends.google.com/trends/explore?date=all&geo=US&q=d...