Without seeing your issue it’s difficult to give a definitive answer to your question.
Could you please send us some screenshots of the problems? Also, provide us with a page url.
I tried to add those css codes in the Custom CSS section, please see the attachment. Then I clicked save options, then refreshed my website, the wishlist is still there under ‘my account’, please let me know if I missed any steps.
Can you please share valid WP-ADMIN Login details of your Site so that we can proceed further and check the issue on your Site and assist you accordingly?