diff --git a/source/libs/executor/src/tfill.c b/source/libs/executor/src/tfill.c
index d30c1fbfa1..78ecb02b93 100644
--- a/source/libs/executor/src/tfill.c
+++ b/source/libs/executor/src/tfill.c
@@ -293,7 +293,9 @@ static int32_t fillResultImpl(SFillInfo* pFillInfo, SSDataBlock* pBlock, int32_t
     int64_t ts = ((int64_t*)pTsCol->pData)[pFillInfo->index];
 
     // set the next value for interpolation
-    if ((pFillInfo->currentKey < ts && ascFill) || (pFillInfo->currentKey > ts && !ascFill)) {
+    if (pFillInfo->currentKey < ts && ascFill) {
+      copyCurrentRowIntoBuf(pFillInfo, pFillInfo->index, &pFillInfo->prev);
+    } else if (pFillInfo->currentKey > ts && !ascFill) {
       copyCurrentRowIntoBuf(pFillInfo, pFillInfo->index, &pFillInfo->next);
     }