Hey just here to report the same issue with my auto-contribution. I’ve included a shot of the Rewards page along with the notification. The tokens in the wallet are all from the token grants, and this is on Brave for Windows Version 0.57.18 Chromium: 71.0.3578.80 (Official Build) (64-bit). Also, no monthly recurring tips outside of the auto-contribute.
I have experienced the same issue on Brave on two different computers. I got the 35 BAT grant on both browsers and set the auto-contribute to 20 BAT, and on the contribution dates for both browsers I got the same notifications about insufficient funds described by others in this thread. I had no other contributions scheduled other than the 20 BAT auto-contribution.
Also, after the auto-contributes failed, I did try to tip a content creator just to see if anything worked, and the tip did work. So it seems only the auto-contribute function is broken.
Btw, both of my browsers that are failing to auto-contribute are Version 0.58.18 Chromium: 71.0.3578.98 (Official Build) (64-bit) for Win10, and all of the BAT I have is from a grant.