If there is an amount in box 173 of your Schedule 3 (Capital Gains), it means you either:

1. entered an Amount for eligible property from box 26 in the Footnotes of the T3 section, or
2. entered Farming and fishing income eligible for the capital gains deduction from the disposition of ECP in the Capital Gains section.

If you entered an amount in either of those boxes by mistake and you have yet not filed your return, you can delete that amount in Wealthsimple Tax. If you have already filed your return, you should change your return to report box 173 as $0 (or the relevant amount in your situation).