https://www.canada.ca/en/immigratio...artner-children/track-update-application.html
Withdraw your sponsorship application
You can withdraw your sponsorship application at any time before your spouse, partner or child becomes a permanent resident of Canada.
To do so,
send us your request and include:
- your name
- your date of birth
- your complete address
- the date the application was sent
- your client ID number, which is your unique client identifier (UCI) (if you know it)
- the type of application (for example, sponsorship of my spouse)
- a copy of the electronic payment receipt
If your sponsored relative becomes a permanent resident before we get your request, you can’t withdraw the application. You’ll have to respect your sponsorship obligations.
DM is not the point in time that you become a Permanent Resident. It requires either a Port of Entry landing or a "landing" at an IRCC office in Canada.