diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index ea8464f..20648a1 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -754,7 +754,7 @@
     {
         mbedtls_ssl_print_extension(
             ssl, level, file, line, hs_msg_type, extension_type_table[i],
-            extensions_mask & ( 1 << i ) ? "exists" : "does not exists", extra );
+            extensions_mask & ( 1 << i ) ? "exists" : "does not exist", extra );
     }
 }