Imgur now blocks several VPNs and have issues loading embedded previews in several fediverse platforms. So instead of using imgur, you could use one of the following alternatives for uploading your images.
https://postimages.org/
https://imgbox.com/
https://imgbb.com/
https://www.imagebam.com/
Seems to be blocked for a friend from the philippines too iirc. Combined with other replies saying they can access it from some of these, I assume that list is outdated.
Website works for me here in the Philippines.