Your Tamagotchi has to be at least 5 years old for the Matchmaker to come. A.K.A the Band Manager.
The times he comes to bring a marriage partner is 12:30pm and 4:30pm. If in your band you have a band member of the opposite gender they will come and propose to your Tamagotchi at 8:00pm. Someone said that one time the band manager came at 6:30pm at generation2.
Sometimes, for strange reasons I do not know, it happens on other ages. The ages are 5,6,7,8. And you also have to set the time a minute ahead. Hope it works soon and you have to keep tryig because it takes a log time sometimes.
Your Music Star has to be 5 yrs old to see the Matchmaker. If your Tamagotchi is 8 yrs ol, doesn't have a mate yet, and don't want it to be an oldie, a boy/girl from your band will come to your apartment @ 8:00 and offer himself/herself as a mate. Hope I helped!