The animation should look like a tapering arrow. At both ends of the arrow there will be white dots; a small one on the left, which is the starting point, and a larger one on the right which is the end point.
When the end dot is active, it will be red rather than white.
What you MAY have done - and if so you won't be the first to have done it - is to drag the callout back to the starting point on the canvas while the end point dot was still red. If so, you've told Camtasia to animate from the starting point to... the starting point. Consequently there won't be any movement.
Double click on the animation arrow, which should take you to the end point of the animation. See where the callout is then. Assuming it's at the starting point, drag it across to the end point again (while the dot is still red).
Once an animation is applied to a callout. The timeline indicator is properly positioned. And the callout or any media for that matter. Whatever it is you are attempting to animate. Is highlighted in the canvas area. You are good to go.
The timeline indicator can be a country mile away from the actual callout or media you are making animation adjustment to. I created an image to try to show you where I'm coming from.
If the timeline indicator is positioned before or after the callout as in the image. The only thing you will be able to see in the canvas area is the bounding box surrounding the callout. So if you were making adjustments to opacity and scale. Having the timeline indicator not positioned over the top of the callout would make these adjustments impossible, as you can see the text. Unless you already had a number in mind.
In general, I don’t think there’s many instances that it makes any sense to make any adjustments with the playhead not positioned directly over the callout. The main reason I was pointing that out? This is a good thing to be aware of. Because if you inadvertently highlight any form of media that has a animation applied to it. And managed to highlight it in the canvas area. If you make changes in the property's panel. That callout or piece of media could be out of sight and out of mind further up for down the timeline. And you could be accidentally applying changes.
In 99+ % cases, you will highlight any form of media on the timeline before you start working in the properties panel again. That will remove focus from the previous callout/media.
But if you’re not thinking about it in the moment. You can be easily making changes to a callout or other media that is out of sight. If you haven't highlighted another form of media.
This still happens to me when I’m working in Premier Pro. I start adjusting a property and it doesn’t happen before my eyes. Sometimes I adjust more than one property before I realize I’m changing the properties of another form of media. Ctrl+Z solves the problem. This is how most video editing programs work to the best of my knowledge.
Let us know if this resolved your issue.