Counselors log in at https://app.benefitkitchen.com/agency/login. Click "Open Cases" in the upper righthand corner and then click "Assume Case". Enter the Account Number (or the client's email address) and PIN of the case you want to assume and that person will become part of your Open Cases list.
You can also add a new case, by clicking the "Add New Case" button. You'll be prompted for the client's email address or mobile number. Be sure to use a verified email address or phone number if you want to ensure that your client can gain access to their account via the "magic link" signin option.