Strange problem by updating characterstic Value

Hi,

   We have a requirement that a Characterstic has to be updated in Valuation of Specification . This update should only happen when user makes a specific status change in specification with new change number.

     we have used C1F5_SPECIFICATIONS_READ to read the valuation with change number and C1F5_SPECIFICATIONS_MODIFY with change number to update Valuation.

This logic has been implemented in Method AT_SAVE_CHECK of Exit EHSS_SPEC_CHECKS .

   This solution is working in most of the cases( 98 % of cases ). But in one or two cases valuation is not getting updated and it has still old value.

Update failure is happening irrespective of users and it happens only 1 time when user tries 10 times. ( for example )

I have checked AUSP table. AUSP has an Entry for new change number.( RECN & ACTN Combination ).

  But this entry contains old Value. ( ATWRT Field ).

Thanking you,

Regards,

  Satya