Hello Everyone,

I am having trouble while downloading exporting the xls file from SALES > REPORTING >SALES 
I have my custom modules installed, but there is no customization due to which this error may arrive. This error only shows on the production server, it doesn't occur on local server.
The error says "Error:
block

undefined"
The log shows no error.
And this error only occurs when one specific product is selected in the table. if i filter out the product and remove from that pivot view of report then the file downloads.
Its been 3 days now and i am still tracing the issue.