The handful of problems that come up most, and what actually fixes them.
A page opens but is empty
The page exists, but the feature that fills it is switched off. Check Plugin Manager for that plugin, and General Settings → Page Settings to confirm the right page is assigned to the right role (shop, blog, tracking…).
A page says the feature is not included
The plugin is either not in your plan (upgrade to add it) or is in your plan but not yet activated in Plugin Manager.
My edits are not showing on the site
Save in the builder, then reload with a hard refresh. If the site still looks old, clear the cache in General Settings → Cache Settings.
Images are missing or slow
Check the image is still in Media — deleting a media item removes it everywhere it was used. For slowness, re-upload photos at a sensible size; a camera-resolution image in a small slot is the usual cause.
Emails are not arriving
Configure General Settings → Email Settings with real SMTP details and send the test email. Form submissions are always stored in the admin, so nothing is lost while email is broken.
My site is not in Google
New sites take days to weeks to appear. Check, in order: indexing is enabled on your plan, the site is not marked hidden in your dashboard, the page is not set to noindex on its SEO tab, and the sitemap is submitted in Search Console.
Something looks wrong after changing theme
Section designs differ between themes. Open each page in the builder and check the sections that used to sit in your old theme's layout; a section your new theme does not style will look plain.