Teacher 2 tries to delete by id the teacher's material - Unexpected Behaviour

[Tatyana-Kravchenko]

Teacher created course (course id: {{courseIdForMaterials}})
POST {{host}}/api/v1/courses
Request Body
{
"title": "How to create test cases1 {{coursePostfix}}",
"description": "Basic course about test design technique",
"visible": true,
"categoryId": {{categoryIdForMaterial}}
}
Teacher added a material in this course
POST {{host}}/api/v1/courses/{{courseIdForMaterials}}/materials
{
"title": "Additional material {{materialPostfix}}",
"data": "stringstri",
"order": 5
}
Id the created material was saved in environment {{aterialIdTeacherToDelete}}

Teacher 2 tries to delete by id the teacher's material
DELETE {{host}}/api/v1/courses/{{courseIdForMaterials}}/materials/{{MaterialIdTeacherToDelete}}

Tests:
pm.test("Status code is 403", function () {
pm.response.to.have.status(403);
});

pm.test("Response time is less than 1000ms", function () {
pm.expect(pm.response.responseTime).to.be.below(1000);
});
pm.test("Check the text error message is correct", function () {
const jsonData = pm.response.json();
pm.expect(jsonData.errors).equal("You're not owner of this course, you can't change/remove it")
});
Actual behavior

1. Status code is 200
2. Response time is less than 1000ms
3. Teacher 2 deleted the teacher's material by id
   {
   "result": "Success: record was removed."
   }

Expected behaviour

1. Teacher 2 doesn't manage to delete by id the teacher's material
2. Statuse code is 403
3. Response time is less than 1000ms
4. The text error message ("You're not owner of this material, you can't change/remove it") is correct

Screenshots
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