In Chrome goto the menu “People->Add Person” and create a new ”test” chrome profile. Alternatively if Menus are not enabled look for the avatar (normally in the Chrome title bar) which will allow you to create/switch profiles.You will then be given a new Chrome browser screen and asked if you want to login. You don't need to do this if you don’t want to. In the new Chrome browser tab go to your normal gmail and login.
Depending on the version of Chrome you have installed and which Operating system you are using, the mechanism to access new Chrome profiles may vary.
Once you have done that you will need to install Sortd in this new Chrome profile by going to www.sortd.com and downloading Sortd again. This should then open a new tab with your email in it along with Sortd (you can close the first tab you opened). You can then try and login/activate Sortd.
If Sortd wasn't working on your primary profile and it does work in this new profile - something has possibly become corrupt with your cookies or data in your main/normal profile (in which case you should delete your cookies), or another Chrome Extension or Plugin is preventing Sortd from working correctly.