On some Individual licenses, you can forego the lock to a specific computer by connecting to the internet on launch. This is called Login Named User, or LNU for short. When using LNU your MathWorks account credentials will be used to verify your license. If you have enabled LNU on your license, you can install MATLAB on a flash drive and run MATLAB on any internet-connected computer.
Since you already have a Login Named User and following the correct steps, I suggest you contacting the MATLAB Licensing support team at Mathworks Support who can help you in solving this problem.
