I got 99 prosperity ... But I don't know must do what ....?

You probably have forgotten about one rookie you need to recruit.

Here is a list of them:
Betamon - Talk to him and he will re-gain his memories then join
City - He makes the item tend. (A mini Item Shop)
Location - Tropical Jungle

Palmon - Fight. Win.
City - Upgrades Meat to Giant Meat (And also sells you each Giant Meat for 500
BITS)
Location - Bottom of Native Forest

Kunemon - Give him anything eat-able Item and fight him. Win.
City - Opens a little passage to Digimon Bridge (by the restaurant where there
Were plants)
Location - Kunemon's Bed

Agumon - Just fight him on the first screen after you leave the city. Win.
City - He opens the Item Keeper
Location - Just leave the city and you _can't_ miss him!

Penguinmon - Have a match of Digimon Curling and win. (First try is free; if you
Lose the first time he will charge one Fish of any type for a re-match.)
City - Opens the Curling Arena inside Greymon's Arena.
Location - Freeze Land

Patamon - When you find him on Gear Savanna, he will want to battle. Win. Then
He will want to battle again. Win. And then he will ask for another try. Again,
Win. *If you stop between battles, the next time you meet him, you will have to
Battle three times again.)
City - He opens the Item Shop or takes place of other Shop Keepers! (The Item
Shop takes place of the Item Stand. And more Items will become avaible for
Sale.)
Location - Gear Savanna

Elecmon - Let him shock you three times.
City - He thinks the city is too dark. So if you go to the screen with the
Fountain at night, there will be lights on the floor.)
Location - Gear Savanna

Gabumon - After finding him, win the battle. (Remember: Size doesn't matter!)
City - Helps Drimogeomon find better items. (Useful ;)
Location - Misty Trees

Biyomon - When you find him, you will play a Mini-Game. The game's object is to
Trap Biyomon on a corner! To win that, go to a corner and tell your Digimon to
Go to the other. When Biyomon comes running at you, he will try to run, but then
Your Digimon will trap him.
City - He opens the Item Shop or takes place of other Shop Keepers! (The Item
Shop takes place of the Item Stand. And more Items will become avaible for
Sale.)
Location - Gear Savanna

There is also the possibility of you forgetting to recruit a useless champion as they are also worth 1 point compared to the rest who are worth 2.

Here is a list of them:
Leomon - After having 40+ Prosperity Rate, go the Drimogeomon's Cave and a part
Were a Drimogeomon was digging, it will be opened. There you will find his
"Stone Tablet". With that item in hand, go talk to him and give him the stone.
City - Stays by the Birdramon on Birdra's Transport (useless)
Kokatorimon - At Misty Trees, there is a screen with some frozen Digimon (maybe
Petrified?). If you go to that screen in the morning, a Kokatorimon should be at
The top of the screen. Fight and win.
*NOTE* This is a very good chance to learn Megalo Spark
Statue - Makes a Scare Crow by the Toilet. (No one is sure if he is useless but I think he is.)

This is from an faq that I have. I take no credit in the details but for me this has always worked.

Hope this helps,
Raj21994