export – Unable to download the exported files

When I try to download the export file following errors throw up:

The webpage at https://example.com/example_admin/admin/export_file/download/key/e96e56437082201cf67598aa719e389dd43e9c11649fd63df8cd0bb0adaccfcd/?filename=stock_sources_20210620_070435.csv might be temporarily down or it may have moved permanently to a new web address.

And when you give the export folder access using this command you can then download the file:
sudo chmod -R 777 export

We are using Magento 2.3.6 and Alicloud Server with ngnix.

Which access should be given to the php user so that exported files are automatically available.