data exceeds Limit

I'm facing the same issue.

It's a bug

https://www.reddit.com/r/PowerBI/comments/16hpklb/data_exceeds_limit_on_a_2mb_xlsx_with_2500_rows/

This is a known issue.

Issue ID:  498

Title:  Export to CSV file truncated at 300 rows

Description: When you select Export data on a tabular visual's options menu and choose to export to a CSV file, the resulting downloaded file is truncated to 300 rows, rather than showing all the available rows.

Status:  Active

Reference URL:  https://learn.microsoft.com/en-us/power-bi/troubleshoot/known-issues/known-issue-498-export-csv-file-truncated-300-rows?wt.mc_id=fabric_inproduct_knownissues

Additional workaround:  Use DAX Studio to export data from selected Visual to CSV or Excel.

Hi herman_ng ,

As foodd  said, this is a known issue. And we have submitted this issue internal to confirm, would update here as soon as possible if there is any update about it. 

Best Regards
Community Support Team _ Rongtie

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

Hi herman_ng ,

This issue has been resolved. You can verify it. If you have any questions, please leave a message. Thank you for your empathy.

Best Regards
Community Support Team _ Rongtie

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

Hi herman_ng ,

This has now been fixed, please use the latest version of desktop

Best Regards
Community Support Team _ Rongtie

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

Look for any error messages or notifications that might provide specific information about what went wrong.
Ensure that your data is loaded correctly in Power BI. If there are any errors during the data loading process, it may prevent you from exporting the data. Check the "Data" view in Power BI Desktop to verify that your data is loaded without errors.
Make sure that the data types of the columns you're trying to export are compatible with the CSV export. For example, if you have columns with complex data types like images or objects, they might not export properly to CSV.
Special characters- Ensure that your data doesn't contain any problematic characters.
Verify that you have the necessary permissions to write to the directory where you're trying to save the CSV file. Also, make sure the file path you specify is correct and that the directory is not read-only.
When exporting, ensure you are using the correct export options. For instance, make sure you are not limiting the export to a specific selection or filter in your report that might exclude data.