Negative Modifiers no longer work in 1.16.1 or 1.16.2

Whenever I used the /give command, I would create cursed weapons with negative modifiers. For Example, Goliath's Sword was an Iron Sword that would deal 12 damage but half the speed of the one holding it. However, the negative speed modifier no longer works in 1.16.2. What gives?

 

"/minecraft:give Rexis102 minecraft:iron_sword{display:{Name:'

{"text":"Goliath\'s Sword","color":"dark_purple","bold":true}

',Lore:['

{"text":"[Cursed]","color":"dark_red","italic":false}

']},RepairCost:9999,Unbreakable:1b,AttributeModifiers:[

{AttributeName:"generic.attackDamage",Name:"generic.attackDamage",Amount:12,Operation:0,UUIDLeast:531288,UUIDMost:452413,Slot:"mainhand"}

,

{AttributeName:"generic.movementSpeed",Name:"generic.movementSpeed",Amount:-.5,Operation:2,UUIDLeast:453387,UUIDMost:109304,Slot:"mainhand"}

]} 1"

 

Here is the command I used