diff --git a/app/api/routers/milestones.py b/app/api/routers/milestones.py
index fd48653..0729f37 100644
--- a/app/api/routers/milestones.py
+++ b/app/api/routers/milestones.py
@@ -7,6 +7,7 @@ from app.core.config import get_db
 from app.api.deps import get_current_user_or_apikey
 from app.api.rbac import check_project_role
 from app.models import models
+from app.models.milestone import Milestone
 from app.schemas import schemas
 
 router = APIRouter(prefix="/projects/{project_id}/milestones", tags=["Milestones"])
@@ -16,7 +17,7 @@ router = APIRouter(prefix="/projects/{project_id}/milestones", tags=["Milestones
 def list_milestones(project_id: int, db: Session = Depends(get_db), current_user: models.User = Depends(get_current_user_or_apikey)):
     """List all milestones for a project."""
     check_project_role(db, current_user.id, project_id, min_role="viewer")
-    milestones = db.query(models.Milestone).filter(models.Milestone.project_id == project_id).all()
+    milestones = db.query(Milestone).filter(models.Milestone.project_id == project_id).all()
     return milestones
 
 
@@ -24,7 +25,7 @@ def list_milestones(project_id: int, db: Session = Depends(get_db), current_user
 def create_milestone(project_id: int, milestone: schemas.MilestoneCreate, db: Session = Depends(get_db), current_user: models.User = Depends(get_current_user_or_apikey)):
     """Create a new milestone for a project."""
     check_project_role(db, current_user.id, project_id, min_role="mgr")
-    db_milestone = models.Milestone(project_id=project_id, **milestone.model_dump())
+    db_milestone = Milestone(project_id=project_id, **milestone.model_dump())
     db.add(db_milestone)
     db.commit()
     db.refresh(db_milestone)
@@ -35,7 +36,7 @@ def create_milestone(project_id: int, milestone: schemas.MilestoneCreate, db: Se
 def get_milestone(project_id: int, milestone_id: int, db: Session = Depends(get_db), current_user: models.User = Depends(get_current_user_or_apikey)):
     """Get a milestone by ID."""
     check_project_role(db, current_user.id, project_id, min_role="viewer")
-    milestone = db.query(models.Milestone).filter(models.Milestone.id == milestone_id, models.Milestone.project_id == project_id).first()
+    milestone = db.query(Milestone).filter(models.Milestone.id == milestone_id, models.Milestone.project_id == project_id).first()
     if not milestone:
         raise HTTPException(status_code=404, detail="Milestone not found")
     return milestone
@@ -45,7 +46,7 @@ def get_milestone(project_id: int, milestone_id: int, db: Session = Depends(get_
 def update_milestone(project_id: int, milestone_id: int, milestone: schemas.MilestoneUpdate, db: Session = Depends(get_db), current_user: models.User = Depends(get_current_user_or_apikey)):
     """Update a milestone."""
     check_project_role(db, current_user.id, project_id, min_role="mgr")
-    db_milestone = db.query(models.Milestone).filter(models.Milestone.id == milestone_id, models.Milestone.project_id == project_id).first()
+    db_milestone = db.query(Milestone).filter(models.Milestone.id == milestone_id, models.Milestone.project_id == project_id).first()
     if not db_milestone:
         raise HTTPException(status_code=404, detail="Milestone not found")
     for key, value in milestone.model_dump(exclude_unset=True).items():
@@ -59,7 +60,7 @@ def update_milestone(project_id: int, milestone_id: int, milestone: schemas.Mile
 def delete_milestone(project_id: int, milestone_id: int, db: Session = Depends(get_db), current_user: models.User = Depends(get_current_user_or_apikey)):
     """Delete a milestone."""
     check_project_role(db, current_user.id, project_id, min_role="admin")
-    db_milestone = db.query(models.Milestone).filter(models.Milestone.id == milestone_id, models.Milestone.project_id == project_id).first()
+    db_milestone = db.query(Milestone).filter(models.Milestone.id == milestone_id, models.Milestone.project_id == project_id).first()
     if not db_milestone:
         raise HTTPException(status_code=404, detail="Milestone not found")
     db.delete(db_milestone)