diff --git a/pkg/icassigner/action.go b/pkg/icassigner/action.go
index 2892563..7ca0cdd 100644
--- a/pkg/icassigner/action.go
+++ b/pkg/icassigner/action.go
@@ -60,13 +60,9 @@ func (a *Action) Run(ctx context.Context, event *github.IssuesEvent, labelsInput
 	}
 
 	// check if someone from the team is already assigned (skip in this case)
-	for _, m := range teamMembers {
-		for _, a := range event.Issue.Assignees {
-			if a.GetLogin() == m.Name {
-				log.Printf("Found assignee %q which is member of the matched team %q. Stopping\n", m.Name, teamName)
-				return nil
-			}
-		}
+	if assigned, teamMember := isTeamMemberAssigned(teamMembers, event.Issue.Assignees); assigned {
+		log.Printf("Found assignee %q which is member of the matched team %q. Stopping\n", teamMember, teamName)
+		return nil
 	}
 
 	// Log the known team member names.
@@ -255,3 +251,15 @@ func convertLabels(labels []github.Label) []string {
 
 	return labelStrings
 }
+
+func isTeamMemberAssigned(teamMembers []MemberConfig, assignees []*github.User) (bool, string) {
+	for _, m := range teamMembers {
+		for _, a := range assignees {
+			if strings.ToLower(a.GetLogin()) == strings.ToLower(m.Name) {
+				return true, m.Name
+			}
+		}
+	}
+
+	return false, ""
+}
diff --git a/pkg/icassigner/action_test.go b/pkg/icassigner/action_test.go
index 4707c77..4b6895a 100644
--- a/pkg/icassigner/action_test.go
+++ b/pkg/icassigner/action_test.go
@@ -19,6 +19,8 @@ package icassigner
 import (
 	"fmt"
 	"testing"
+
+	"github.com/google/go-github/github"
 )
 
 func TestFindTeam(t *testing.T) {
@@ -93,3 +95,69 @@ func TestFindTeam(t *testing.T) {
 		})
 	}
 }
+
+func TestIsTeamMemberAssigned(t *testing.T) {
+	teamMembers := []MemberConfig{
+		{Name: "Alice"},
+		{Name: "Bob"},
+		{Name: "Charlie"},
+	}
+
+	testCases := []struct {
+		name           string
+		teamMembers    []MemberConfig
+		assignees      []*github.User
+		expectedResult bool
+		expectedName   string
+	}{
+		{
+			name:           "No assignees",
+			teamMembers:    teamMembers,
+			assignees:      []*github.User{},
+			expectedResult: false,
+			expectedName:   "",
+		},
+		{
+			name:           "Assignee matches team member",
+			teamMembers:    teamMembers,
+			assignees:      []*github.User{{Login: github.String("Alice")}},
+			expectedResult: true,
+			expectedName:   "Alice",
+		},
+		{
+			name:           "Case-insensitive match",
+			teamMembers:    teamMembers,
+			assignees:      []*github.User{{Login: github.String("bob")}},
+			expectedResult: true,
+			expectedName:   "Bob",
+		},
+		{
+			name:           "No matching assignees",
+			teamMembers:    teamMembers,
+			assignees:      []*github.User{{Login: github.String("Unknown")}},
+			expectedResult: false,
+			expectedName:   "",
+		},
+		{
+			name:           "Multiple assignees, one matches",
+			teamMembers:    teamMembers,
+			assignees:      []*github.User{{Login: github.String("Unknown")}, {Login: github.String("Charlie")}},
+			expectedResult: true,
+			expectedName:   "Charlie",
+		},
+	}
+
+	for _, testCase := range testCases {
+		t.Run(testCase.name, func(t *testing.T) {
+			result, name := isTeamMemberAssigned(testCase.teamMembers, testCase.assignees)
+
+			if result != testCase.expectedResult {
+				t.Errorf("Expected result to be %v, but got %v", testCase.expectedResult, result)
+			}
+
+			if name != testCase.expectedName {
+				t.Errorf("Expected name to be %q, but got %q", testCase.expectedName, name)
+			}
+		})
+	}
+}