My sim won’t stop sneak walking but I don’t want to get rid of her relationships

@jasinoz  Try evicting the sim and placing her back in the house.    You can evict the entire household or only the one sim, or the one sim plus an adult if the affected sim is still a teen.  If you do this in one Edit Town session, without saving the sims to the in-game bin and placing that bin copy, the evicted sims will keep their jobs and relationships, although they'll lose their promised wishes and opportunities.

Or, if you use mods, there's an NRaas DebugEnabler command to fix a walkstyle.  Click on the sim and select NRaas > DebugEnabler > Options: Smartphone > Reset Walk.