Screenshot feature needs that spyzie is still running at the same moment when you hit "take screenshot" command.
However most of the time Spyzie is sleeping on target phone, only running when it is collecting data from target phone. This is because running 24/7 on target phone will drain the battery too quickly, which makes phone owner aware there is something wrong.
Spyzie might have been killed on the target phone by other security apps. Or some app is preventing Spyzie to start running. That is why it did not work.
You need to uninstall and install Spyzie on target phone manually again.