Hi @Roma Patel ,
I tested it in my environment and the situation is the same as yours.
According to the Embed web part article description, the embed code needs to be based on iframe. Maybe your embed code conflicts with the design of SharePoint. Based on the observation of the content you want to link to, it is found that the content displayed in the web part is the content within the original link content tag. If you can edit the content of the original link, you can try keeping only the content you need. If you want to figure out the root cause, you can try creating a new service request in M365 admin center as an admin, and more professional will help you.
(Microsoft 365 admin center ->> Support ->> Help & support)
Thanks for your understanding.
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