I am on my Server and it is Vanilla, but it doesn't work.

[fengcheng0126]

Possibilities:
I am on minehut and when I changed it to vanilla, it didn't update from spigot.
I still have lifesteal plugin activated, even though it is vanilla
Or I still have gear on me(unenchanted iron leggins and boots)

Description:
I followed every step. I didn't do anything except start with an enchant(dummy item) and then block off 1 bookshelf. When I got 14, it told me no possible seeds.
Here is me trying to make it work, but it didn't: https://www.youtube.com/watch?v=Vc3mdqV5hmI
the video tutorial I watched said I have to enchant a dummy item for my current seed to reset. I use bottles of enchanting to give myself exp, so could it be that? I have no mending items. Also, should I use the square layout or the 2 high setup for the bookshelves?
Here is something i found that Earthcomputer replied to 3 years ago:

Earthcomputer commented on Aug 8, 2019
I've just tried it on a local Spigot server and it worked. Try using clientcommands and see if it works on that. Since clientcommands is a mod, it has the ability to tell you exactly why it failed.
He says it worked for him on local spigot servers. How come? Doesn't spigot fix the predictability of the enchantment seeds? Or something like that. So is running spigot an option for me if I want the lifesteal plugin? I really want to use this for my lifesteal server. I am going to try to use it in vanilla while disabling and deleting plugin files.

[JaaiDead]

Time Stamp on the video?

[fengcheng0126]

mostly 2min+ and ends 2 min before the stream ends. BTW im on 1.18.2