Edit: Jan drinks more coffee and says Andrew beat me to the reply, waves at Andrew.
That’s a commercial theme and those aren’t supported here.
https://themeforest.net/item/rockit-now-music-band-wordpress-theme/3278167
Have you considered asking the theme author for support? That was part of what you paid for when you made that purchase.
https://chimpstudio.co.uk/support
Side note: Your site’s HTML indicates that you got may have gotten that theme from an “alternate” location (not from the author). You’re running an old version of that theme and the CSS is definitely modified.
If that’s case then you really don’t want to do that. There are Very Bad People? who insert malicious code into those themes and Very Bad Things? can happen to your site.
See this excellent article on that topic.
https://www.chipbennett.net/2010/12/10/only-download-wordpress-themes-from-trusted-sources/
