"Not able to create" is a little vague. Specifics please... 🙂
Does the "New Table" option appear when you right click? If not, sounds like a bug in SSMS, try the classic steps (a) make sure you are current on updates (b) reboot and (c) when all else fails reinstall.
Or do you get an error when you try to click "New Table" ?? If so, what error and when?
If it says you are not logged on as database owner or systems admin, sounds like a security issue.
Are you sure you are right clicking on the same database and the same server as where you are running your script?
Sorry to give you back questions to a question.
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