Sage 300 2018 Error on export button

Custom report developed for AR invoices . User enters parameters and executes reports and all the data comes on print preview , approx 15 pages . 

As soon they click  on export button  the following error is received. generally user tends to run the report and export to excel data only for further analysis.

sage 300 premium  2018 with PU3, SQL 2017 and Server 2016. Clients use sage using workstation setup. Sage Workstation Setup installed again once but didn't fix issue.

appreciate fixes for this.