Action not allowed alert while login in Geo POS alert appears when you try to access the application with a different URL, it is a security feature to prevent CSRF attacks.
Case 1:
Your application is installed https://www.example.com but you are trying with https://example.com
Case 2:
Your application is installed https://example.com but you are trying with https://www.example.com
Case 3:
Your application is installed https://example.com but you are trying with http://example.com
Case 4:
You have enabled hard caching on your server. Hard caching starts security token caching, the application does not allow to login with expired security tokens.