Wow.  How does that happen?

Could this be it? What is it btw and how do I fix it

I know about the lack of information.  I have seen HOV signs that state MC OK up here but I haven't been down to your area since the 'change'..

You will have to find it yourself after cleaning.  Sounds like that will be easy to pin point,

I've rode in the hot lanes/HOV up here in NOVA and did not use an ezpass but my bike is registered with the system.  I don't remember getting any bills..

If you are registered, and the transponder is not read, the license plate reader SHOULD still link to your account and act the same as using a transpoder.  But, at least in Hampton Roads, I don't think you can create an account without them sending you an EZpass transponder, which they apparently expect you to mount and use.  I scanned through their documentation and FAQ's and can't find any mention of exactly what happens when the transponder is not read.  I can only find anecdotes elsewhere.

Presumably if the tag is not read while in the express lanes, the system will assume NON-HOV mode and charge the full amount of the express lane toll at the time based on vehicle class (which for a motorcycle is zero dollars) to the plate holder's account.  Have no idea if a notification or warning is issued.  If there is no account for the plate holder, it will charge that plus hefty fees which escalate over time ("pay by plate" or "Missed-a-Toll") to the owner of the car via mail.

So it does make one wonder why bother with a transponder or account if you are a motorcycle and use ONLY Express Lanes without using toll bridges and tunnels.  I thought of this, but wanted to be on the safe side with no surprises.  There might be some fee for non-account-holders.  It is amazing there is no info on that.