Error while editing an automaticlly populated record of a custom infotype

Question

hi,
a query in HR ABAP.
i have created a custom Infotype to store the CTC details of an employee. this custom IT needs to get the records auto populated, when they are created in Infotype 0008.
i have used the exit. EXIT_SAPFP50M_002  inside which  an include program is written  :ZXPADU02
using this, the records made to get create automatically in the custom IT.
but when we try to modify or delete those records thru the tcode PA30,
it does not allow to do so and throws a standard error message. as  below.
Specified subtype is invalid
Message no. PG088
please help me out to fix this issue.

Answer 1

the exact point of the std error is,
i do the folowing steps.
1)_ for auto creating a record in custom IT Pa**** , i goto transaction, PA30, create record in IT 0008 with a basic Pay., click on save.
on saving , the EXIT_SAPFP50M_002 is called where i ve written a Z inlcude Program, which inserts the record in custom IT PA****.  this is successful.
2) when i try to change or delete the same record which i ve created as above, through the Tcode PA30 for custom IT, PA
****, i get the error.
hope the problem is clearly mentioned