child theme breaks when updating parent theme to latest version

when i update my site to the latest version of the idlly template. it crashes my site.
i was told there was an error in my functions file in the child theme but cannot verify.

Hey there,
I hope you’re doing well today

It seems you’ve added some modifications to the site not native to the theme.
If you have customized the theme to your liking, your site may crash if some core code has been changed.

Please ensure to do a backup of your website.
You can create a staging environment using this plugin: WP STAGING – Backup Duplicator & Migration – WordPress plugin |
You can use this test updates.

Please submit the issues you’re having in detail to our GitHub.

Best Regards,