Please format your code we cannot help you with code like this

 

Because on line 12 you are adding location of event-block to {orange glazed terracotta.generator::1::*}
But I think, tier 2 is {orange glazed terracotta.generator::2::*}

Code (Text):

1. on right click on white glazed terracotta:
2.     if player is sneaking:
3.         if {cooldown.%player%} is true:
4.             send "%{prefix}% Slow down!"
5.             cancel event
6.             stop
7.         if {cooldown.%player%} is false:
8.             if {money.%player%} is more than 99:
9.                 set event-block to orange glazed terracotta
10.                 send action bar "&3You upgraded your gen for 100 money" to player
11.                 remove event-block's location from {white glazed terracotta.generator::1::*}
12.                 add event-block's location to {orange glazed terracotta.generator::2::*}
13.                 remove 100 from {money.%player%}
14.             else:
15.                 send action bar "&cYou need 100 money to do this!" to player
16.                 set {cooldown.%player%} to true
17.                 wait 4 ticks
18.                 set {cooldown.%player%} to false

Better use index of list as location of block, and simply increment number value by index
Something like:
add 1 {orange glazed terracotta.generator::%location of event-block%}
And don't use dot in lists, use
{money::%uuid of player%}, instead {money.%player%}