diff --git a/library/ssl_tls13_keys.c b/library/ssl_tls13_keys.c
index 765b7fd..3306d62 100644
--- a/library/ssl_tls13_keys.c
+++ b/library/ssl_tls13_keys.c
@@ -1166,7 +1166,7 @@
                                    app_secrets );
     /* Erase master secrets*/
     mbedtls_platform_zeroize( &ssl->handshake->tls13_master_secrets,
-                              sizeof(ssl->handshake->tls13_master_secrets));
+                              sizeof( ssl->handshake->tls13_master_secrets ) );
     if( ret != 0 )
     {
         MBEDTLS_SSL_DEBUG_RET( 1,