Snapshot Not Backing up with Run Now or Automatically

Snapshot will not backup to Dropbox regardless of whether I have it set up automatically or by clicking Run Now.

I have implemented the feature described in this post below, and it still has no effect.

https://premium.wpmudev.org/forums/topic/snapshot-not-backing-up#post-1193352

Please advise how to fix this.

Thanks for your help!