AE telling me Dropbox login is wrong! It's not!

I've set up Dropbox long ago, email and pw has been the same forever. When I'm trying to get into the field (tomorrow morning!), I am trying to use, as instructed in AE, SetUp>TimeTracker>Manage TT, and I have my device listed, synced it earlier to AE, all my cards showed up, no problem. Then, I got my TT email, clicked the link, taken to Safari webpage (still in 10.6.8 os), and there are 5 steps. I am already done with 1-4, but on step 5, filling in my device name, then my DRopbox email and pw, it keeps rejecting the email or password as "incorrect." It's not. I'm stuck! Any advice this evening most welcome, I've got animals to see on the farm tomorrow, and it'd be nice to bill while I'm there.
Thanks kindly.