How do I restrict emails to only allow manually added/existing customers?

[Ieva Katiliute]

We have spam coming through and creating tickets.. I would like to only allow existing or manually added customers to be allowed to create the tickets. Is there a way to filter this? allow/block list is not a good solution since 'allow list' just makes sure the emails go through but it doesn't reject the rest. 

Please let me know what your solution is and I will test it out! 

Thank you so much 

[Jack Brickey]

You should configure your project with customer permissions as illustrated below. Any email request sent to your project's email channel from an address that is not a current customer will be denied.