I don't know what is that problem

[Avvoyer]

How can I fix that?

URL: avvoyer.com

[huongpho]

I saw it's working without issue, both mobile and desktop 

[Avvoyer]

Thanks for replying, but I've already switched themes. I'm star all over again, and hoping that it will be fixed. 🙂

[StephensWorld]

That's a custom-coding edit gone wrong. It's telling you in the error message exactly where to look for the issue: card-collection template, on line 81. 

If you remember making any changes to the card-collection template, then you'll probably want to revert them, by switching to an earlier version of the template in the template's history. If you don't remember making the changes, then you'd want to hire someone who knows custom coding, to help try and fix the issue for you. Alternatively, you can always add a new/fresh copy of your theme to the site, and then set it up again -- and the issue should resolve itself. 

[Avvoyer]

That print screen was already taken on a new fresh theme, I didn't change a character at the card-collection template and it doens't seen to have any issue at line 81, it's just as it should be. I think there was a mistake in the activation of the Flickity template, I'm starting all over again. Thanks for replying!