update was terminated - conversion no number

dear all,

while doing Me38 transaction , after updating the details i clicked on save.

it saved. Again i press enter.

i got the error 'express document: update was terminated received from author'.

error analysis shows : conversion no number error.

but this error is not coming in dev or qas server. it is coming only in production..

how to rectify it ???

waiting for reply,

Thanks,

Dhivya N.