Material number (&1) is not the same as construction type (&2)

What causes this issue?

Synchronous maintenance of material numbers and construction types is
recommended in Customizing for the equipment type, or to be precise: If
the material number is maintained, the construction type should have
the same value.

System Response

The equipment construction type has the value &V2&. The system
indicates that to maintain synchronicity, you should change the
construction types to &V1&.

How to fix this error?

Check whether the construction type should be changed and, if
necessary, make these changes manually.

Error message extract from SAP system. Copyright SAP SE.