Cannot find a saved email attachment

I’m experiencing difficulty saving an email attachment in the native email application. On opening the email, I locate the attachment at the bottom of the email and then I tap on it. I then get a full screen view of the attachment, in my case a PNG file. With some fiddling, I managed to find the *** context menu and I am faced with Save;Save All;Share;Share all; Print and Download again - I have clicked on Save and Save all as well as Download again - all offering me no clue as to where it is saved - because I’m not prompted with any message - the only Option that seems to work is Share all. Now I have tried searching in the Storage for the file - alas - nothing. What am I doing wrong. This should be a simple easy and painless operation to do.

I tried it also. Do not use the native email app, but used my Gmail account.
When I open the .PNG file and click on the three dots, I choose Save.
In Storage I find the .PNG file in the map ‘Download’.

When I delete the file and want to save it again, it doesn’t work anymore??? I cannot save 2 times the same file… it seems…