This issue is explicitly addressed in guide 005010X221. Section 1.10.2 states "...These solutions may not be the only possible solutions within an ASC X12 835 transaction. They are, however, the only solutions for the business situations identified that are compliant with this implementation guide. Creation of 835 transactions that are not consistent with the information here is prohibited under this implementation." Section 1.10.2.8 (Reversals and Corrections) spells out specific requirements for sending a reversal in the 835. All of those requirements must be met for any reversal of a previous claim payment. While one of those requirements is to send the CLP segment with CLP02="22", that is not the total of the requirements. Only meeting that requirement is not good enough. Another requirement is that if the original adjudication included an adjustment (a CAS segment), then a reversal must negate that prior adjustment (CAS segment).

Please review section 1.10.2.8, in detail, for ALL of the related requirements.