[stonics]

Hello,
I am completely new to all this. I just got my Kindle paperwhite 4th gen yesterday and was very excited to start putting old ebooks of mine on it, I was following a tutorial online to convert books for the kindle.
Everything went really well yesterday and I managed to get my books on the kindle, but that's when I noticed that my covers weren't of the same height. So I got on Calibre and stated to download the covers via the "Download cover" button, then right click on the cover that I needed then "View cover at full size" and then "Save as". That worked really well yesterday, I managed to download covers, resize them and then upload them again.
But after updating to the new Calibre this morning I got this error message (I get the error when I try to save the cover generated by Calibre on my pc):

calibre, version 5.4.1
ERROR: Unhandled exception: <b>FileNotFoundError</b>:[WinError 2] Le fichier spécifié est introuvable: 'C:\\Users\\stoni\\Downloads\\ooo.png'

calibre 5.4.1 [64bit] embedded-python: True is64bit: True
Windows-10-10.0.19041 Windows ('64bit', 'WindowsPE')
('Windows', '10', '10.0.19041')
Python 3.8.5
Windows: ('10', '10.0.19041', '', 'Multiprocessor Free')
Interface language: None
Traceback (most recent call last):
File "calibre\gui2\image_popup.py", line 129, in save_image
File "calibre\gui2\win_file_dialogs.py", line 296, in choose_save_file
File "calibre\gui2\win_file_dialogs.py", line 232, in run_file_dialog
File "calibre\gui2\win_file_dialogs.py", line 230, in fix_path
FileNotFoundError: [WinError 2] Le fichier spécifié est introuvable: 'C:\\Users\\stoni\\Downloads\\ooo.png'

Is it because of updating? Or did I do something wrong? I first had my files on the cloud, but I read on forums that that wasn't good so I moved everything, but still had the same issue. I then uninstalled Calibre and deleted all possible files that had to do with it (via %appdata% etc.). And then redownload but I still have the same error message.
I have no books on Calibre right now, and I'd like to have no issues before I really start putting books on it, else it'd have other effects.
Sorry if I'm putting this in the wrong thread or if this has been adressed before, just spent the whole afternoon looking online but finding nothing so this is a last resort aha.
Thanks in advance for any help xx