Maintenance package & not contained in strategy &

What causes this issue?

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

System Response

How to fix this error?

Check whether the maintenance package short text is correct. If not,
overtype it with the correct values.
If you do not know the short text, select the desired maintenance
package using the possible entries help function.

Error message extract from SAP system. Copyright SAP SE.