The work centers have different standard value keys (& and &)

What causes this issue?

You want to replace a work center. The new work center has a different
standard value key as the old work center. A standard value key defines
standard values with a dimension, performace efficiency rate and
activity type.

System Response

If you want to keep the differing standard value keys, the system
deletes all standard values in the operations where you replace the
work center or resource. The program deletes standard values with a
dimension, performance efficiency rate and activity type. The values
from the new work center are not copied.

How to fix this error?

Replace the old work center with a work center with the same standard
value key,
<ZH>or</>
change the standard value key of the new work center. Note that the new
work center may already be used in other task lists.

Error message extract from SAP system. Copyright SAP SE.