And it’s easy

And i put the skulls on last

Hmmm

Any blocks under the wither’s arms

No

Then it can only be a glitch

Try summoning it somewhere else

Ok will do gotta finish my geography lesson first

Everyone is studying geography now

Anyways, if you are in minecraft Java Edition, and not in hardcore, and cheats enabled, copy paste the code below to the chat input:

/summon minecraft:Wither 1

Or if in bedrock:

/summon wither ~ ~ ~

Wither: "Just five more minutes, Mom..."