Martial Arts Tourney Issue

[Wonderbugg]

I have a Martial Arts Grandmaster sim who has an 'Opportunity' to win a tournament called 'Try the tournament'.  My issue is, this opportunity came up while I was back home and after attaining Grandmaster level.  I've travelled back to China and when I use the phone to 'Challenge Spar Tournament Contender', I get a sim named 'Bao Louie' that immediately responds with 'Something suddenly came up and I can't make it'.  I have tried at different times in the day and get the same response.  At night, I get the 'Try calling during normal hours'.
How do I get past this?

EDIT:  I have tried the resetSim 'cheat' to no avail.  I called the sim one day at 5am (Too late to call), 7am, 9am, 11am, 1pm, 3pm, 5pm, 7pm, 9pm, 11pm & 1am (Too late to call).  Then I tried another day at 6am, 8am, 10am, noon, 2pm, 4pm, 6pm, 8pm, 10pm midnight @ 2am (Too late to call).  Those were the only 'solutions' I found to this problem.  nothing has worked and I cannot progress in this line.  Any help would be greatly appreciated.

EDIT #2:  Found on a different site.  I purchased a vacation home and called for the next contender from there.  No issues.

[saltpastillen]

The reason your sparing sim didn't show up was probably that he has the loner trait. If this happens again, find out where he lives, visit him at home and challenge him there. This has happened to me a number of times and this workaround fixes it.

The reason it worked once you bought a vacation home was probably because your sparing partner was a different sim.

[Schipperke]

A common reason for Sims to not show up is if they are one of the shop merchants.  Those poor Sims never get to go anywhere!  If that's the case, you can go to them.  It's a while since I've had this happen, but I seem to remember that you can go to the shop and challenge them there.