Some templates have album covers with fixed ratio ( horizontal or vertical). In such case simply use crop&reframe tool. The option creates a duplicate of the image that you can reframe and set as album cover, while hiding it in the album itself.
Find out more on our YouTube channel here:
Focus points: https://youtu.be/U2yMx9nA2dU
Crop & reframe tool: https://youtu.be/lIeHEuHyIKY