diff --git a/blockcheck.sh b/blockcheck.sh
index 6d1e8d0..65a3391 100755
--- a/blockcheck.sh
+++ b/blockcheck.sh
@@ -293,7 +293,7 @@ curl_test_https_tls12()
 
 	# prevent using QUIC if available in curl
 	# do not use tls 1.3 to make sure server certificate is not encrypted
-	curl -${1}Ss --max-time $CURL_MAX_TIME $CURL_OPT --http1.1 --tlsv1.2 $TLSMAX12 "https://$2" -o /dev/null 2>&1 
+	curl -${1}ISs --max-time $CURL_MAX_TIME $CURL_OPT --http1.1 --tlsv1.2 $TLSMAX12 "https://$2" -o /dev/null 2>&1 
 }
 curl_test_https_tls13()
 {
@@ -302,7 +302,7 @@ curl_test_https_tls13()
 
 	# prevent using QUIC if available in curl
 	# force TLS1.3 mode
-	curl -${1}Ss --max-time $CURL_MAX_TIME $CURL_OPT --http1.1 --tlsv1.3 $TLSMAX13 "https://$2" -o /dev/null 2>&1 
+	curl -${1}ISs --max-time $CURL_MAX_TIME $CURL_OPT --http1.1 --tlsv1.3 $TLSMAX13 "https://$2" -o /dev/null 2>&1 
 }
 
 pktws_ipt_prepare()