Import data to existing schema from dmp file ORA-39083: Object type ALTER_PACKAGE_SPEC failed to create with error:
ORA-01775: looping chain of synonyms
Failing sql is:

ALTER PACKAGE "XZB"."P_IATA"   COMPILE SPECIFICATION     PLSQL_OPTIMIZE_LEVEL=  2    PLSQL_CODE_TYPE=  INTERPRETED   
PLSQL_DEBUG=  FALSE    PLSCOPE_SETTINGS=  'IDENTIFIERS:NONE' REUSE
SETTINGS TIMESTAMP '2015-07-24 05:12:12'



I get above error when I try to import schema which is already existed.
Check the documentation of the current database release

Oracle Database Error Messages
12c Release 2 (12.2)
E49883-13

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It  may contain outdated but nevertheless useful information: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.