We recommend always flushing the capsule every time you make a coffee. If you don't, sometimes the pod can dry to the outlet and get stuck.
If a pod is already stuck, pull up the lever and push the button for a small coffee, and the capsule should be removed with help from the water pressure. If this doesn't work, try pouring some water on the capsule in order to soften it up before trying the same thing again.
Any issues, let the team know at shop@grind.co.uk.