Opacity Mask path isn't moving

[Kyle Marcoe Visuals]

When I start to do the opacity mask path transition, the very first one would work perfectly fine. When I do the next frame, I would expand the blue line and the black mask wouldn't follow along or would be slowly behind and I would have to expand the blue line even more to get it covered up. What can I do to fix this?

In this picture, it shows the tiny mask in the top right corner, I tried expanding it and here it is. It won't follow along....

[Kyle Marcoe Visuals · Accepted solution]

I figured it out, I had it on slow speed duration. I needed it to be on normal speed duration then it would work.