No subtypes can be maintained for infotype &1

What causes this issue?

You have entered subtype &V2& for infotype &V1&. However, no entries
are allowed to be made for individual subtypes of this infotype because
the <LS>Country-dependent subtype</> indicator is not flagged in the
<LS>Infotypes - Dialog/Database Assignment</> table T777D. Only one
entry (input = "*") can be made for all subtypes.

How to fix this error?

Add the missing entry to table T777D <LS>Infotypes - Dialog/Database
Assignment</> or contact your system administrator.

Error message extract from SAP system. Copyright SAP SE.