Check the documentation of the current database release
Oracle Database Error Messages
12c Release 2 (12.2)
In the documentation of the current release you will find only
ORA-01775: looping chain of synonyms
This is not helpfull (The 11.2 documentation does not contain the message at all). In this case check the
documentation of the 9i release.
Oracle9i Database Error Messages
Release 2 (9.2)
Part Number A96525-01
It may contain outdated but nevertheless useful information:
ORA-01775 looping chain of synonyms
Cause: Through a series of CREATE synonym statements, a synonym was defined
that referred to itself. For example, the following definitions are circular:
CREATE SYNONYM s1 for s2
CREATE SYNONYM s2 for s3
CREATE SYNONYM s3 for s1
Action: Change one synonym definition so that it applies to a base table or view and retry the operation.
So check if the package specification of XZB.P_IATA contains such a synonym.