Multisite sub domain not creating sites

Hi all, I’m new to here. I created a multi-site for teaching kids by tutors. One man company looking to help kids learn about engineering.
All looked good during install, but when I create a new site WP goes through the motions but the new site is not created.
I put a wild card for sub domains.
The site is https://www.early.engineering and I want to be able to create sub sites such as https://www.dundee.early.engineering
Can anyone provide support please?
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