Can you please confirm the number of columns you are trying to export and if it is possible to try with less number of columns and see if this works or not? If this doesn't, please open a ticket with support with details like:
1. Report (name and location) you are trying to export.
2. Instance URL.
3. Has this worked previously for any other report?
Thank you for the response and as far as only 200 records getting displayed. This is working as designed. There is a section in the documentation on how to change the default limit that is put on the query.
Take a look at the screen shot below for more information:
Once you have made the above change, there could be a possibility that the number of records you are trying to export may increase in future, which may result in error related to Memory (Out of Memory). To avoid this from happening, please do raise a ticket and get the JS maxMB value confirmed and updated accordingly.
Thank you for reaching out to Forum. And per your request, can you please confirm if this is an issue with Exporting data from an Out of the box Report or a Custom Report?
In this situation, you would need to open a request with Adobe Campaign Support. As this could be an issue with the JS allotted size. Support team would get this checked and will help you get it upgraded. And hopefully, this shall resolve the issue.
If this is related to a custom report, there could be many reason and custom report needs to be checked with PS/Consultant. For more information on this, please refer to this documentation (check section Memory allocation): Actions on reports