Element & from expression & is incompatible with structure &

What causes this issue?

The expression &V2& provides for access to an individual field of the
reference structure of element &V1&.
The structure &v3& is provided for reading element &V1& (via binding
definition or setting parameters of expression evaluation). But, the
element &v1& is incompatible in the current container instance with the
structure &v3&.

System Response

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

How to fix this error?

Error message extract from SAP system. Copyright SAP SE.