Hustle e-mail opt-in pop up not working

Hustle e-mail opt-in popup not working. On submit it is giving following error in the console.

jquery.js?ver=1.12.4:2 Uncaught Error: Syntax error, unrecognized expression: .inc_optin_*|FNAME|*_error
at Function.fa.error (jquery.js?ver=1.12.4:2)
at fa.tokenize (jquery.js?ver=1.12.4:2)
at fa.select (jquery.js?ver=1.12.4:2)
at Function.fa (jquery.js?ver=1.12.4:2)
at Function.a.find (jquery-migrate.min.js?ver=1.4.1:2)
at n.fn.init.find (jquery.js?ver=1.12.4:2)
at n.fn.init.a.fn.find (jquery-migrate.min.js?ver=1.4.1:2)
at a.fn.init.n.fn.init (jquery.js?ver=1.12.4:2)
at new a.fn.init (jquery-migrate.min.js?ver=1.4.1:2)
at n (jquery.js?ver=1.12.4:2)