Section title: Requests for Interpretation
Respond to HL error

How can an HL error be responded to? In particular, consider a 005010X279 270 eligibility request with HL02 value that doesn't mathc any HL01 value.
TA1, 997, and 999 cannot describe this error. Nor do I see a way that the 271 response can indicate an error with the 270, as the AAA segments require a valid HL hierarchy.
(Morever, this appears to be the situation all transactions sets using the HL level.)


A 999 using the CTX segment would be the best possible approach, identifying in the CTX01 that a situational trigger failed, and the related IK3, IK4 and IK5 segments. Using a 271 and the AAA segment would not be viable as indicated in the comment as the HL’s would have to be identified and there’s no way to do such a thing using the AAA segment.