Uncaught TypeError in WP-ADMIN

Ivory search is throwing the following error in the admin dashboard. It’s across the board, not on any one page. To ensure it was Ivory Search, I disabled all the plugins and enabled them one at a time to find it.

We noticed this because we tried to go to Appearance -> Customize to update our theme and the left hand menu stopped at ‘widgets’.

jquery.min.js?ver=3.6.0:2 Uncaught TypeError: this._addClass is not a function
    at $.<computed>.<computed>._create (accordion.min.js?ver=1.12.1:9)
    at $.<computed>.<computed>._create (jquery-ui.js?ver=5.8:415)
    at $.<computed>.<computed>._createWidget (jquery-ui.js?ver=5.8:585)
    at new $.<computed>.<computed> (jquery-ui.js?ver=5.8:376)
    at HTMLDivElement.<anonymous> (jquery-ui.js?ver=5.8:531)
    at Function.each (jquery.min.js?ver=3.6.0:2)
    at s.fn.init.each (jquery.min.js?ver=3.6.0:2)
    at s.fn.init.$.fn.<computed> [as accordion] (jquery-ui.js?ver=5.8:523)
    at HTMLDocument.<anonymous> (ivory-search-admin.min.js?ver=4.6.5:1)
    at e (jquery.min.js?ver=3.6.0:2)

Can this be resolved please.