The first step: describe it well.
Your building
City, province, foundation material if known, whether the basement is finished and how the wall can be accessed.
The issue
Location, when you noticed it, water and changes. Keep your photos available to share with the team during follow-up.
Your plans
Mention a planned sale, renovation or other work. This helps the team understand your constraints before discussing timing.
For background on moisture: Government of Québec.