If you encounter an error like the image above, hopefully this article will be a solution.
Cause: the uploaded file size exceeds the predetermined configuration.
Solution: change the upload file size.
Here are the steps :
1. Login to Plesk Panel.
2. Select Domain and click on the domain that is experiencing problems, then click PHP Settings.
3. At upload_max_filesize, change the upload size from the default 2M to the desired upload size, then click OK.
Please try and good luck, thank you.