The agent that answered is telling the sender to go directly to another host (DIAMETER_REDIRECT_INDICATION) -- normal behaviour of a redirect agent, not an error by itself.
Where you see it
In the Result-Code or Experimental-Result-Code AVP of a Diameter answer (S6a, S6d, Gx, Gy, Cx…).
What to check
Check that the sender then re-sends the request to the host named in Redirect-Host.
Look at the Origin-Host of the answer: an intermediate agent (DRA/IPX) and the home HSS mean different owners of the problem.
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