Hi everyone... Here is a quick video where I show you how to fix YouTube's comment failed to post error. Below are the instructions on how to fix the issue if YouTube isn't letting you post your comment on a video:
1. Let the advertisement finish playing or wait until it allows you to skip it... then skip the advertisement.
2. Pause the video.
3. Go back to the comment section and leave your comment!
That's it... pretty simple fix but an annoying problem if you can't figure it out. Let me know if this doesn't work for you. Thanks!