Text field (keyword) does not exist in ABAP Dictionary

What causes this issue?

The required text 1=short, 2= medium, 3=long, 4=header, does not exist
in the text fields of the corresponding data element or type.

How to fix this error?

If you flag the text field as a variable by entering space in the 'mod'
column, the longest text field from the ABAP Dictionary that fits will
be used. If the shortest text field is too long, a warning is
displayed. If there is no text field at all (1..3), the text field is
set to modified.

Error message extract from SAP system. Copyright SAP SE.