I am still not clear on what happened from the description. It sounds to me like you created a second Microsoft Windows 10 user account or profile on your Windows 10 computer which does not have the same administrator privileges that the original account or profile has. You performed a clean install of Instant Text 7 Pro under that account profile.
I am guessing that Instant Text Support wanted you to do a clean install of Instant Text 7 Pro as a new Instant Text 7 user, not create a new Microsoft Windows 10 user profile, but I have not seen instructions such as you received and I could be wrong.
I am sorry that I cannot be of help.