Not only imgur.com, but I remember that I got an error using another hosting service, I don’t remember it specifically, but I did not face any problem with TalkImg.com, so even if you have an image hosted in hosting services, it is better to re-upload it using TalkImg.com.
Since using the TalkImg image hosting service, I have never experienced a problem like the one experienced by the OP.
I can say, talkimg hosting works perfectly for me.
Even though I didn't experience any problems using Talkimg image hosting, I also found several other people's image posts on several boards that looked damaged and displayed the words image proxy invalid image.
Is it possible that my internet network is weak so the display of other people's image posts is invalid even though the image hosting they use is imgbb.