Dear Venkat,
If you can reproduce this issue, maybe we can debug and investigate further.
But if it's a one time issue, there is only few thing we can do:
1. You can check if there was RFC user maintenance or network maintenance during error time.
2. Please check if there is any dump created at error time in ECC.
3. Please check if anyone set breakpoint in CRM/ECC side which may stop replicating.
I hope it helps.
BR
Dean Yan