You need to click "use bonus money" when you want to place the bet, because I face a same problem when I didn't click the "use bonus money". Don't forget the requirement of the free bet are the odds must be above 1.50x and wagering 10x ($100.54). I have wagering $47 until now, let's see if I can reach the minimum requirement

is your $47 also calculated with your signature payment ($25)?. I mean your balance appears to be $72 in profile or split each other?.
I do have some question for this casino.. I had made out $20 on that free $10 im sure im not totally busted but why my balance shows $0? Where are those bonus amount go?
Have you checked in payment history?. If not the case like Royse said, maybe the bonus is still there (bug). In the top left you to have also to click the balance tab and check the possibility inside in
Bonuses tab.