Cannot delete or update a parent row: a foreign key constraint fails

This is a scenario

Table (Telephone)

• id
• Number

Table (Person_has_Telephone)

• Person_id(PK)
• Telephone_id(PK)
  • Constraint - Table Telephone

....

Delete all Person_has_Telephone where Person_id = 1, 

Delete all Telephone where Id = Telephone_id from Person_has_Telephone <--- fail and got the above error..

* Telephone Table is the Parent table, isn't it?

What is wrong with it? How can I fix this?

Thanks