Unable to progress Legacy of Vaal questline

Im in Jiquani's Mechanarium, i have the small soul core, i have the quest helper telling me to place the soul core in the stone altar, but no matter how much i click it, doesnt trigger. Ive relogged, switcher characters, closed reopened the game, fully cleared and killed everything, dropped and picked up the core multiple times, the stone altar wont trigger for me. Only way to fix it was an instance reset, as iut appears like alva can body block the altar when you summon her