diff --git a/source/libs/executor/src/filloperator.c b/source/libs/executor/src/filloperator.c
index 9b0b43b6c4..dc6d7a791e 100644
--- a/source/libs/executor/src/filloperator.c
+++ b/source/libs/executor/src/filloperator.c
@@ -166,18 +166,20 @@ static void revisedFillStartKey(SFillOperatorInfo* pInfo, SSDataBlock* pBlock, i
     } else if (ekey < pInfo->pFillInfo->start) {
       int64_t t = ekey;
       SInterval* pInterval = &pInfo->pFillInfo->interval;
-
+      int64_t    prev = t;
       while(1) {
-        int64_t prev = taosTimeAdd(t, pInterval->sliding, pInterval->slidingUnit, pInterval->precision);
-        if (prev >= pInfo->pFillInfo->start) {
-          t = prev;
+        int64_t next = taosTimeAdd(t, pInterval->sliding, pInterval->slidingUnit, pInterval->precision);
+        if (next >= pInfo->pFillInfo->start) {
+          prev = t;
+          t = next;
           break;
         }
-        t = prev;
+        prev = t;
+        t = next;
       }
 
-      // todo time window chosen problem: t or prev value?
-      if (t > pInfo->pFillInfo->start) t -= pInterval->sliding;
+      // todo time window chosen problem: t or next value?
+      if (t > pInfo->pFillInfo->start) t = prev;
       taosFillUpdateStartTimestampInfo(pInfo->pFillInfo, t);
     }
   }
diff --git a/tests/script/tsim/query/interval.sim b/tests/script/tsim/query/interval.sim
index e2b0d219cb..135fcc8591 100644
--- a/tests/script/tsim/query/interval.sim
+++ b/tests/script/tsim/query/interval.sim
@@ -206,6 +206,19 @@ if $desc_rows != $asc_rows then
   return -1
 endi
 
+print ================= step11
+
+sql create database if not exists test0828
+sql use test0828
+sql create stable st (ts timestamp, c2 int) tags(tg int)
+sql insert into ct1 using st tags(1) values('2021-08-01', 0)
+sql insert into ct2 using st tags(2) values('2022-08-01', 1)
+sql select _wstart, _wend, count(*) from st where ts>='2021-01-01' and ts < '2023-08-28' interval(1n) fill(value, 0) order by _wstart desc
+print $rows
+if $rows != 32 then
+  return -1
+endi
+sql drop database test0828
 print =============== clear
 #sql drop database $db
 #sql select * from information_schema.ins_databases