Every tour in Golf Clash has a maximum number of available trophies.

Tour 1 "Beginner" - 20 Trophies
Tour 2 "West Coast" - 50 Trophies
Tour 3 "Asia Pacific" - 100 Trophies
Tour 4 "6 Star Hotel" - 200 Trophies
Tour 5 "World Links" - 300 Trophies
Tour 6 "U.S. Champions" - 500 Trophies

You can still earn Coins from completed tours but be careful as you can also lose your current Trophies!

You can see how many Trophies you have in each tour on the tour select screen.