Specify a time period to the next read access

What causes this issue?

The event queue is read at defined intervals. However, you have not
specified a time interval for the read accesses.

System Response

The input is not accepted.

How to fix this error?

Enter a time period.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.