I have a cloud instance with a small team. One user who just joined, and signed in for the first time, did not get a personal space created for them, and cannot create a personal space.
In the menu under their icon in the top right of the interface there is the option "Add personal space..."; when clicked it takes them to the expected "Create a personal space" overlay, but when they click "Create" the system thinks for a second, then closes the overlay without creating the personal space and without returning any error message.
The user can create other spaces but not a personal space.
Potential cause of the problem:
When this user first logged in there was already a space with their same name, and therefore the same name Confluence would attempt to use when creating their personal space . Assuming this was creating a conflict, I deleted that space, then went into the Confluence settings and permanently deleted the space.
This hasn't fixed the problem. The option to "Create a personal space..." is still there in the user's menu, but the system still won't create that user a personal space.