rev_slider not able to install
The plugin rev_slider is not able to work property suddenly. When I try to install, the message mentioned "Invalid license code. Please make sure that your purchase code is used only on this domain. You can check it at: api.muffingroup.com/licenses" . I did check License is fine after got this message. And there is a message shown on Betheme plugin page "Server limits: if you are not sure about server's settings and limits, please activate necessary plugins only."
What should I do about this issue? Thanks a lot.