According to: https://gdpr-info.eu/art-7-gdpr/
1.The data subject shall have the right to withdraw his or her consent at any time.
2 The withdrawal of consent shall not affect the lawfulness of processing based on consent before its withdrawal.
3. Prior to giving consent, the data subject shall be informed thereof.
4. It shall be as easy to withdraw as to give consent.
Thus… please offer your members a way so they can delete their account and next time let people themselves choose if they would like to signup or not instead of signing them up yourself so they only have to click a link to acknowledge the signup they never asked for. In the EU this sort of behavior is even forbidden A notification about this behavior will also be sent towards several DPA’s in the EU so they be aware about this.