Mathcad Express Prime 10.0.1.0 does not allow me to set values anymore

I downloaded the Express version, I still have 9 days free trial. However I cannnot write code anymore. Everytime I write something it is shown in an opaque color, and the program does not  allow my to do any operations, it does not show me values. Does someone know where the problem lies? I worked two days without an internet connection with Mathcad, I believe some issue with the license might be the problem. I am happy for any solution suggestions. I urgently need to finish my work and I cannot right now due to this issue.