What gameplay feature is this bug affecting?
Sparring with sub males

What's the issue? Please include any error messages you receive and as much detail as possible.
Yesterday, I checked my den page to spar with one of my subs. The button to spar didn't show so I thought I must've done it already and forgotten about it. So I checked again today right after rollover and it didn't show again. The page just shows the same but without the sparring section.

Any links relating to this bug? For example, if a particular lion is bugging, what is the link to that lion?
N/A

Any screenshots you can provide us with?
N/A

Please provide us with step by step explanation how this bug happened so we can attempt to replicate it. If it's complex, please include screenshots where possible:
All I did was log on and go to my den page. My den page looks like I've already done the sparring, but I know for a fact that I haven't.