Graph upload failure

Hi Stardog collegues,

We have a twice-weekly automated procedure in place to update our graph in Stardog Cloud. For simplicity's sake, the procedure simply drops the old graph and replaces it with an updated one. On the last run, we received the following error:

Could not upload content graph_output/entity.jsonld.gz: [500] TXHRE2: There was a fatal failure during preparation of 6c65605b-4a45-4535-a38d-152f7ab13cbe: Illegal character in path at index 7: Concept URI

In the past, problems with our procedure have sometimes been caused by an audit log that didn't get rotated. Could this be the culprit again? For context, our procedure uploads several different jsonld files, and this (the one noted in the error message) was the only one that failed.

Thanks for any help you can offer!
Rob