diff --git a/firebase_messaging/fcm.py b/firebase_messaging/fcm.py
index f13155f..612950e 100644
--- a/firebase_messaging/fcm.py
+++ b/firebase_messaging/fcm.py
@@ -26,7 +26,7 @@ def fcm_register(sender_id, token, retries=5, log_debug_verbose=False):
     # first byte of public key is skipped for some reason
     # maybe it's always zero
 
-    private_key = ec.generate_private_key(ec.SECP256R1)
+    private_key = ec.generate_private_key(ec.SECP256R1())
     public_key = private_key.public_key()
 
     serialized_private = private_key.private_bytes(
diff --git a/firebase_messaging/gcm.py b/firebase_messaging/gcm.py
index 1162696..d62c378 100644
--- a/firebase_messaging/gcm.py
+++ b/firebase_messaging/gcm.py
@@ -73,6 +73,7 @@ def gcm_check_in(
             )
             if resp.status_code == 200:
                 acir = AndroidCheckinResponse()
+                break
             else:
                 _logger.warning(
                     "GCM checkin failed on attempt %s out of %s with status: %s, %s",