Within Kolleno you can assign and unassign customers in bulk to a portfolio.

Click into your Customer list and select customers on the left hand side.

Click Bulk Action on the right hand side and choose either "Assign to Portfolio" or "Unassign from Portfolio".

Before choosing the Portfolio you'd like them to be assigned to. Repeat the process if these customers are across a range of Portfolios. Ensure to click Save at the end.

You can then find your Portfolios by clicking your business name in the top left hand side, click Users & Permissions and Portfolios.