diff --git a/library/ssl_srv.c b/library/ssl_srv.c
index ce92f98..7ef263c 100644
--- a/library/ssl_srv.c
+++ b/library/ssl_srv.c
@@ -2745,7 +2745,7 @@
 #if defined(MBEDTLS_SSL_PROTO_DTLS)
     if( MBEDTLS_SSL_TRANSPORT_IS_DTLS( ssl->conf->transport ) )
     {
-#if defined(MBEDTLS_IMMEDIATE_TRANSMISSION)
+#if defined(MBEDTLS_SSL_IMMEDIATE_TRANSMISSION)
         mbedtls_ssl_immediate_flight_done( ssl );
 #else
         if( ( ret = mbedtls_ssl_flight_transmit( ssl ) ) != 0 )
@@ -3810,7 +3810,7 @@
 #if defined(MBEDTLS_SSL_PROTO_DTLS)
     if( MBEDTLS_SSL_TRANSPORT_IS_DTLS( ssl->conf->transport ) )
     {
-#if defined(MBEDTLS_IMMEDIATE_TRANSMISSION)
+#if defined(MBEDTLS_SSL_IMMEDIATE_TRANSMISSION)
         mbedtls_ssl_immediate_flight_done( ssl );
 #else
         if( ( ret = mbedtls_ssl_flight_transmit( ssl ) ) != 0 )