diff --git a/tests/ci/cherry_pick.py b/tests/ci/cherry_pick.py
index d8e4b8fe3a5..d898355db95 100644
--- a/tests/ci/cherry_pick.py
+++ b/tests/ci/cherry_pick.py
@@ -211,9 +211,9 @@ Merge it only if you intend to backport changes to the target branch, otherwise
                 "Assing to assignees of the original PR: %s",
                 ", ".join(user.login for user in self.pr.assignees),
             )
-            self.cherrypick_pr.add_to_assignees(self.pr.assignees)
+            self.cherrypick_pr.add_to_assignees(*self.pr.assignees)
         logging.info("Assign to the author of the original PR: %s", self.pr.user.login)
-        self.cherrypick_pr.add_to_assignees(self.pr.user)
+        self.cherrypick_pr.add_to_assignees(*self.pr.user)
 
     def create_backport(self):
         # Checkout the backport branch from the remote and make all changes to
@@ -249,9 +249,9 @@ Merge it only if you intend to backport changes to the target branch, otherwise
                 "Assing to assignees of the original PR: %s",
                 ", ".join(user.login for user in self.pr.assignees),
             )
-            self.cherrypick_pr.add_to_assignees(self.pr.assignees)
+            self.cherrypick_pr.add_to_assignees(*self.pr.assignees)
         logging.info("Assign to the author of the original PR: %s", self.pr.user.login)
-        self.backport_pr.add_to_assignees(self.pr.user)
+        self.backport_pr.add_to_assignees(*self.pr.user)
 
     @property
     def backported(self) -> bool: