RM unable to generate document/pdf

Team,

We recently migrated our RM project area to a new RDNG server. After migration, we're unable to generate document/pdf from some artifacts. We tried without links, comments, titles etc. The issue happens on a few folders after migration.

We duplicated one of the artifact in the affected folder and all artifacts started working after that. But the next day we're facing same trouble in generating document. I can send the error and also the log excerpt from rm.log if needed.

We're using RDNG 6.0.3.

Could you advise what could be going wrong here?