You can pause Qoins activity simply by turning off AutoPilot.
AutoPilot will pause your savings method from automatically working in the background. You won't see any new deposits to Qoins while AutoPilot is off.
If you'd like to pause your automatic payment: click on your Pay Off Debt goal, and the payment you'd like to pause (if you have multiple payments set up. Next, click "View Payment Options" in the blue outlined box and select "Pause scheduled payments".
Deposits to Qoins already initiated, that were not canceled individually before AutoPilot was turned off, will still go through.