I first noticed this a few days ago (do not recall exactly when because I am not here every day unlike some guys with lots of free time). Scanned recent posts and cannot find that the issue has already been raised.
I've been logged in for about 15 minutes and had to click on "not a robot" about 5 times. I've paid TER over $2k in 13 years and I have to verify that it was not a robot that sent them all that money?
This happened to me once some months ago, then it stopped.
TER is messing with a lot of their code in preparation of the launch of a new version of the site, and it's probably related to that.
...when I'm on TER and the ad blocker is on I get the "robot" question a lot. Now I turn the ad blocker off when I'm on TER and don't have that problem. It could be something like that causing your situation.
I've been using the beta version a lot lately. The robot question (instead of the Captcha like the regular version uses) comes up whenever I communicate with TER.
office computer, which has several layers of security, I get it constantly. However, on my laptop where I have less security, its only occasionally.
Ticket sights use it a lot. It prevents a computer program from tying up good seats at various events.