Levitation doesn't overlay the elytra flying

The bug

In 1.12.2 i was able to use levitation effect to control players' vertical motion. I use chained command to do that:

/execute @e[tag=!declock] ~ ~ ~ detect ~ ~-1 ~ minecraft:diamond_block 0 effect @s minecraft:levitation 1 53

(it will bring me up to 65blocks high)

And in 18w02a, I do that as:

/execute as @a[scores={F=1..}] run effect give @s minecraft:levitation 1 255

/execute as @a[scores={F=1..}] run effect give @s minecraft:levitation 1 100

I also checked it by use this command when i am flying:

/effect give @s minecraft:levitation 1 100