Hello!! I was wondering if someone could help me with a short skript!!

Objective:
Allow a max of 1 shulker box of any color in the players ender chest, if they try to add more, it cancels the event

For MC Version: 1.16.5
Skript Version: Latest of current date 6/12/2021

It would be amazing if someone could provide me with the skript!

Bonus!:
I also want to remove the ability from players to be able to add tnt in shulker boxes

^^ This is what I have for it, but I don't know if it's correct or not

 

Code (Text):

1. on inventory click:
2.   if inventory type of player's current inventory is ender chest:
3.     if amount of shulker box in player's current inventory is more than 1:
4.       cancel event
5.       send "Sorry, but only a max of 1 Shulker Box per echest!!"

I made this but it gives me an error:
Can't compare 'inventory type of player's current inventory' with an item type (admin.sk, line 70: if inventory type of player's current inventory is ender chest:')

--- Double Post Merged, Jun 15, 2021, Original Post Date: Jun 14, 2021 ---

I was able to fix the issue by making it:

Code (Text):

1. on inventory click:
2.   if name of player's current inventory is "Ender Chest":
3.     if amount of shulker box in player's current inventory is more than 0:
4.       cancel event
5.       send "Sorry, but only a max of 1 Shulker Box per echest!!"

However am getting an issue where it won't let me remove the shulker box out of the ender chest. The Max Value does appear to be working properly however it won't let the player remove it from there ender chest to their inventory