Adjust the message clients see when booking a shift, and no candidates are available
Adust this message "unfortunately, there are no candidates currently available for the date and times you've selected."
Step 1:
On your dashboard got to MORE and select GLOBAL SETTINGS

Step 2:
Once you are in global settings, select Jobs, then select Shift Job Settings, then Client Side
Step 3:
Scroll down and you will see this area to adjust the message. 
Step 4:
Once done, click the save icon in the bottom right of your dashboard.