Yeah it looks like the tag was not "locked in" , just typed. At the moment (at least on desktop version) it requires you to hit enter after each tag to save it one at a time, like on yourtube.
It would look like this as you add tags.
I also added in a request for that to be more like we are used to doing it on Steemit.
The tags couldn't be locked in mobile device. I don't know if thats just in my case.