Objects require different request types

What causes this issue?

To edit the selected objects, they must be included in a change
request.
However, the objects cannot be edited in a request with the same
request type.
Conflicts can occur if:
Objects are assigned to different packages
Objects are contained in the object categories "CUST" and "SYST"

System Response

Object editing is terminated.

How to fix this error?

Only choose objects that can be edited in the same request type.

Error message extract from SAP system. Copyright SAP SE.