Webnovel Author: Santu_Banerjee - Fanfic Collection

An Ultimate Skill holder may have the ability to release themselves from the Infinite Prison or potentially break it from inside or outside, depending on the specific capabilities of their Ultimate Skill.

Veldora's powers were restricted while he was imprisoned in the Infinite Prison. The exact limitations aren't explicitly detailed in the series, but it's clear he couldn't use them to their full extent. He was unable to break free on his own, despite possessing immense power and control over space.

ok.

I don't remember exactly, but I think Veldora can't use his skills while in the Infinite Prison.