Rules in Pega Applications are not picking as expected

HI Team,

Email listener is not working as expected.

i tried revalidate and save.

Rule-Service-Email class key—

EmailDefault.ClassDefault.EmailInbound is not a valid entry

Even though this rule is present still am getting above error in email listener form.

Could you all suggest me few solutions

Check the below link and follow the debugging steps , if the email listener has started running on the admin studio.

Verify the requestor credentials in the email listener rule

Pegasystems Documentation?

Thank you