Old conc. req. not running but with same code new conc. req. runs

   Dear All,

We have very old concurrent requests which calls pl/sql block was working since past three years. Suddenly it gets completed with Normal.But with certain data does not get processed.

We submit the new concurrent request calling the same procedure code,gets complted with proper data.

Question is why the old req. is not doing the job? and new one doing the same wihtout any change.

We are on 11.5.10.2 with 10g R4 on Hp-PARISC server.

This is happening for only this req. others are fine.

Does the issue with concurrent manager? Morever, we are running more than 55,000 requests/day.