Pb param Upload media size

[Mika17420]

I try to transfer a PDF file to the image folder of my Joomla 4. But it keeps telling me that the file is too large.
My php settings are good at 8MB. The media/config setting is 4MB. But as soon as I send my pdf which is 1.7 MB it systematically reduces the media settings to 2 MB.
I have several sites and the problem is the same everywhere
an idea ?

[dautrich]

Did you increase at least PHP settings post_max_size and upload_max_filesize ?

[Mika17420]

yes I made this setting.
on the other hand in joomla media param, if I put 0. The value is retained and it blocks according to the size indicated in php upload_max_file.

[Mika17420]

false alarm
after refreshing the page, the value dropped again to 2