Check these in Settings → Website embeds:
The embed is enabled. A disabled embed shows nothing.
Your website is on the Allowed websites list. The embed only shows on the exact domains listed.
www.is optional, but subdomains such asnews.council.gov.ukmust be added separately.The challenges are still approved. A challenge marked Not published is no longer approved for your account and won't show.
The snippet is on the page. Copy it again from Snippet and check it was pasted in full.
If the embed says No challenges are published here at the moment, it's working but has nothing to show.
