So often we are told that, when "used" is past tense, to be sure to include the "d" on "used" with the word "to" after.
...He used to go with her.
...She was used to really good treatment.
The reason we have to be reminded of this is the sound of a "d" at the end of one word and a "t" at the beginning of the next elide; that is, they make one sound.
When the helping verb "did" is in the sentence, there is no "d" on the word "use" just as there is no "d" on any other word with the helping verb "did."
...He wanted to be in the play.
...He intended to be in the play.
...He used to be in the play.
...He did want to be in the play.
...He did intend to be in the play.
...He did use to be in the play.
...Did he want to go with her?
...Did he intend to go with her?
...Did he use to go with her?
Happy punctuating!
Margie