My Blink gave me lots of fits when I had a special character in my wireless SSID name. I took out the "&" character and went to straight alphanumerics and stability increased.
I haven't had any "failed to charge" incidents, but I WAS seeing the screen in 'calibrate' mode a lot and saw a lot of lost wifi symbols (black wifi symbol in lower right corner) even after I removed the "&" character from my SSID. SO, as a test to see if these problems are wifi related (and I'm assuming they ARE), I hardwired my Blink this morning. It's now up and running on the LAN, so we'll see if I see any more of those random 'calibrate' screens.
I was able to run 50' of CAT5e cable plus associated jacks, etc., for just under $50. For me, it is worth the time and effort if I can help Blink put out a better product. I shouldn't HAVE to do this, but I think the Blink unit is head and shoulders above the Clipper Creek unit and I want to see this type of EVSE become the standard, not something that is brushed aside because it was too buggy.
I'll report back here as time goes on regarding the stability of my unit on the LAN. I can already say that the intranet connection data runs MUCH faster. I'm guessing the Blink designers took an 'off-the-shelf' wifi setup and threw it in, not fully understanding all the intricacies that go along with it. (shrug)