Most devices allow you to store multiple eSIMs, but how many you can store depends on the make and model.
Some aloSIM customers report getting the following error when they hit their maximum number of installed eSIMs:
"Can't add plan. To add a new plan, you need to remove your other eSIM mobile plan."
If you see this message on your device, it means you have hit the maximum number of eSIMs, and you need to remove a previous eSIM in order to add a new eSIM.