diff --git a/src/client/src/tscParseLineProtocol.c b/src/client/src/tscParseLineProtocol.c
index e0ee0f6c522423d6da6e8c83e3a7eb98fab43333..f8c634887007a7e6282bda8e59454ca0f2256e2a 100644
--- a/src/client/src/tscParseLineProtocol.c
+++ b/src/client/src/tscParseLineProtocol.c
@@ -1408,8 +1408,12 @@ static bool isTimeStamp(char *pVal, uint16_t len, SMLTimeStampType *tsType, SSml
 
   //Default no appendix
   if (isdigit(pVal[len - 1]) && isdigit(pVal[len - 2])) {
-    if (info->protocol == SML_LINE_PROTOCOL && info->tsType != SML_TIME_STAMP_NOT_CONFIGURED) {
-      *tsType = info->tsType;
+    if (info->protocol == SML_LINE_PROTOCOL) {
+      if (info->tsType != SML_TIME_STAMP_NOT_CONFIGURED) {
+        *tsType = info->tsType;
+      } else {
+        *tsType = SML_TIME_STAMP_NANO_SECONDS;
+      }
     } else if (info->protocol == SML_TELNET_PROTOCOL) {
       if (len == SML_TIMESTAMP_SECOND_DIGITS) {
         *tsType = SML_TIME_STAMP_SECONDS;
@@ -1421,6 +1425,7 @@ static bool isTimeStamp(char *pVal, uint16_t len, SMLTimeStampType *tsType, SSml
     }
     return true;
   }
+
   if (pVal[len - 1] == 's') {
     switch (pVal[len - 2]) {
       case 'm':
@@ -1716,7 +1721,7 @@ static int32_t getTimeStampValue(char *value, uint16_t len,
   }
 
   //No appendix or no timestamp given (len = 0)
-  if (len >= 1 && isdigit(value[len - 1]) && type != SML_TIME_STAMP_NOW) {
+  if (len != 0 && type != SML_TIME_STAMP_NOW) {
     *ts = (int64_t)strtoll(value, NULL, 10);
   } else {
     type = SML_TIME_STAMP_NOW;
diff --git a/tests/examples/c/apitest.c b/tests/examples/c/apitest.c
index 7217de3d55aaeca9bf6ad319ad85248225007e6a..da846de2616abac43d1426e63d9d0d5172c68dee 100644
--- a/tests/examples/c/apitest.c
+++ b/tests/examples/c/apitest.c
@@ -984,7 +984,7 @@ int32_t verify_schema_less(TAOS* taos) {
 
   char* lines2[] = {
       "stg,t1=3i64,t2=4f64,t3=\"t3\" c1=3i64,c3=L\"passit\",c2=false,c4=4f64 1626006833639000000",
-      "stg,t1=4i64,t3=\"t4\",t2=5f64,t4=5f64 c1=3i64,c3=L\"passitagin\",c2=true,c4=5f64,c5=5f64 1626006833640000000"
+      "stg,t1=4i64,t3=\"t4\",t2=5f64,t4=5f64 c1=3i64,c3=L\"passitagin\",c2=true,c4=5f64,c5=5f64 1626006833641000000"
   };
   code = taos_schemaless_insert(taos, &lines2[0], 1, 0, "ns");
   code = taos_schemaless_insert(taos, &lines2[1], 1, 0, "ns");
@@ -1036,7 +1036,6 @@ int main(int argc, char *argv[]) {
 
   printf("************  verify schema-less  *************\n");
   verify_schema_less(taos);
-  return 0;
 
   printf("************  verify query  *************\n");
   verify_query(taos);