Assuming there is a setting in the theme control in the admin panel, and that is what you are using to change the background image; it could be a browser cache issue.  If that doesn't work, you may want to contact the theme dev  It could also be a file type, or file size issue. Try using jpeg, or png file types. If the file size exceeds your server limit, you will need to contact your hosting provider.

Hi Darryl and thanks for your answer.

In first place i flush all caches but dont work, i optimize the size of image and used .jpg, finally i try directly to modify the css rule but still dont works.. i ask now to my hosting provider.

I don't know if you can help me with this another situation that is relate with this topic. I try to change the default icon colors in simplicity theme. i look for css rule but i see they are images in .svg, i change it but dont works and for this moment i can't upload the images. that was the problem? 

I'm really sure that i don't modify the structure of any more that file. 

I'm sorry about my broken english. 

Kind regards,

As for the svg colors; check this post. Remember. You have to set dev mode to true at the very bottom of the config.php file when making any changes via cpanel. Once you are done making changes; go to your site, and refresh any page, then your changes should show. Go back to cpanel, and set dev mode back to false.
If you are unable to upload any files the hosting provider may be able to help, and that is most likely the reason you are having issues changing the background.

https://developers.oxwall.com/forum/topic/55034

Thank you so much! Your awesome! Go oxwall!! 

Hi Darryl, 

Just one thing more, i follow your steps about dev mode and works just for one of icons (photo icons) like and comment doesn't change. I change color in .svg, preserve the name but just no change and i don't know why. maybe that buttons works with a css rule? or is a cache issue? what you think?

Kind regards, 

Is simplicity theme; miniic_comment and miniic_like.svg

You can double check your theme's images folder to make sure the images are the new ones that you changed.
Once you have the new images there setting dev mode to true clears the site cache after you refresh the page, so if the new images were name the same as the original to replace them, it should show on the site.
The css just calls for the .svg icon, and sets placement. It has nothing to do with actually styling the icon.

I do this:

1. I set Dev mode true to config.php 
2. Upload the two .svg files and replace them.

3. I set dev mode again false.

4. Refresh my page. 

5. Doesn't work. 

Please let me know what i do wrong. thanks again.

In the steps you listed you would set dev mode back to false after refreshing your site.

1. I set Dev mode true to config.php 
2. Upload the two .svg files and replace them.

3. Refresh my page.

4. I set dev mode again false.

No, i do it in that order and i see the file in cpanel like i want 

but is not like that in the webpage:

The ones in the attachment is the miniic_set not the miniic_like.  The miniic_set has both the like, and comment icon.

and that's it! Works now.. i change the file and works. Your awesome.. im sorry bother you with this! thanks so much!

That's cool. When there's something I know I try to help. Maybe you'll be able to help someone now as well.