plottools is not responding in Matlab18a? How to solve Matlab18a connector issue?

When I start matlab I see connector issue.

When I check by the command I see the following:

connector on

Error in Connector: Did not start the server. Desired port was: 31515. Last error was: Server did not respond to initial request: 127.0.0.1:31714

Add-ons

Error in Connector: Did not start the server. Desired port was: 31515. Last error was: Server did not respond to initial request: 127.0.0.1:31714

plottools

Opening plot..not responding i.e. not opening editing tool.

I followed the solution given by the link

https://in.mathworks.com/matlabcentral/answers/258174-error-using-connector-ensureserviceon-when-clicking-get-add-ons

https://in.mathworks.com/matlabcentral/answers/390468-error-in-matlab-r2017b-student-version-did-not-start-the-server-desired-port-was-31515-last-erro

I turned off firewell. Set Java variables. Still problem is not solving.

Please give proper instructions.