When you rename the event, be attentive to the alias - it can’t repeat other aliases or event names.
If you scroll down, you will see the list of blocked events which contains events that were blocked by the system or a customer.
There is a limit of 300 unique event names that we can track simultaneously. If you reach the limit, you can block those active custom events that are currently irrelevant.
To block or unblock the event you need to tap the lock icon.