If you separated or divorced in 2020, the Canada Revenue Agency (CRA) will still require your ex-spouse’s/ ex-partner’s information. The info is needed for a number of reasons, like eligibility for certain credits or deductions, handling property you still own together, etc.
This FAQ has more information: https://turbotax.community.intuit.ca/community/other-income/help/what-do-i-do-if-i-don-t-know-my-spo...
