Problem loading a new header logo

[MichaelUPR]

Hi, I'm new to prestashop and  I'm have problems loading a new logo on my prestashop. When I loaded the new logo and saved the changes, the image disappeared and I got a question mark in place as you can see : 

http://www.uselesspride.com/store/fr/

I've been trying many different formats, different in size, jpg, png, different logos, I tried putting back the old logo, I've tried different browsers (google chrome, firefox, opera...). There is nothing I can do, the question marks remains in place of the logo. I've searched all over google but never found anything really helpful. 

If anyone here can help that'd be wonderful. Thank you.

 

Edited March 8, 2019 by MichaelUPR (see edit history)