Error: Unable to Compute Warp Homography and Camera

Out of nowhere, Mocha Pro plugin (2019.5 in AE 6.1.1 on macOS 10.14.5) said:

Unable to Compute Warp Homography and Camera

While in the Insert Module (for a track and insert that had had no issues previously).
What do I do about this?

I have tried to delete and reimport the PNG file to insert. When I did that, then I got

Layer Overlay Error: Failed to render warp point.

I want to emphasize that this is a track and insert that I’ve had no issues with multiple times of going into Mocha Pro, making adjustments, going back to AE, testing/viewing/rendering out, and back in again. All without any issue.

I have been finding that if you go back and forth between AE and the MP plugin too many times, there is a certain point at which MP will crash or just lose its internal connection to its own database somehow. I don’t know what happens, but several times in the past two weeks I find the plugin just sort of gets too confused and it will lose its place or not know where I left off and will simply stop working.

This error is an example of Mocha getting confused. I’ve gone back and forth between MP & AE and have had no problems with this particular insert. It’ll track wonderfully, I can insert an image or clip (the weird looping thing notwithstanding) and it will be fine then boom, out of nowhere, Mocha Pro just can’t track or follow things any longer. It’s very hard to pin down but it’s happened enough times that I’m now getting very antsy about how often I make corrections to a track or an insert. Over 10 times of making adjustments and Mocha will either crash (there seems to be no crash reporting mechanism built-in) or it just can’t stay connected with its internal database.

That sounds to me like the surface tool is going behind the camera. Can you see the surface tool for the entire track? Are you using a large insert? Usually, that’s what “Unable to Compute Warp Homography and Camera” errors mean.

This has less to do with Mocha Pro getting confused and more to do with being unable to calculate the data because the camera can’t accept “negative” values, and if the surface tool breaks the “camera” plane in Mocha, it gives poor results.

Let me know the answers to my questions above and I will be happy to help you.

Cheers,
Mary

This error just popped up out of nowhere. I can’t get any kind of response from Mocha with this error, nothing happens. I’m new to MP and really don’t know a lot about it yet. But, no, I don’t think the insert is large.
This did happen after I moved the layer with the tracking below another layer in the AE comp. At some point, I also changed the name of that comp, again in AE. It was sometime after moving the layer down and renaming that layer these errors occurred. That’s all I know. Seems odd that would generate the errors I described.
But Mocha Pro has either stopped working (as in, it will no longer respond to changes in a track or a similar anomaly) or it will really crash everything, bringing down AE with it after I do a lot of tweaking (going in and out of MP from the AE comp layer with the track). Somehow it loses its internal connections, whatever they are, and just won’t respond any more or will full-on crash. If I could tell you more, I would, but I’m new to it (using 2019.0 and 2019.5 versions) so that’s it.
If MP generates log files (that you can tell me how to find), happy to send them along.

Can you clear the cache in both AE and in Mocha? And can you go into Mocha and turn your surface tool on, then scrub the timeline and make sure it is visible at all times?