Word Highlight in subtitles in Resolve 20

I tried this the way this Mr Alex Tech tutorial showed me,
but it does not work very well (yet)
I made a (Dutch) subtitle, but the were some mistakes made.
No problem you think. Just change the text till it is right.
I did, but in the video nothing changed.
See the attachment.
Is it a bug? (betaversion) or did I do something wrong?

I made a (Dutch) subtitle, but the were some mistakes made.
No problem you think. Just change the text till it is right.
I did, but in the video nothing changed.
See the attachment.
Is it a bug? (betaversion) or did I do something wrong?