diff --git a/src/internal.c b/src/internal.c
index cd4954713..5e834bc7d 100644
--- a/src/internal.c
+++ b/src/internal.c
@@ -12102,7 +12102,7 @@ static WC_INLINE int DtlsCheckWindow(WOLFSSL* ssl)
             return 0;
         }
 
-        if (window[idx] & (1 << (newDiff - 1))) {
+        if (window[idx] & (1 << newDiff)) {
             WOLFSSL_MSG("Current record sequence number already received.");
             return 0;
         }
@@ -12209,7 +12209,7 @@ static WC_INLINE int DtlsUpdateWindow(WOLFSSL* ssl)
         word32 newDiff = diff % DTLS_WORD_BITS;
 
         if (idx < WOLFSSL_DTLS_WINDOW_WORDS)
-            window[idx] |= (1 << (newDiff - 1));
+            window[idx] |= (1 << newDiff);
     }
     else {
         if (diff >= DTLS_SEQ_BITS)
@@ -12231,7 +12231,7 @@ static WC_INLINE int DtlsUpdateWindow(WOLFSSL* ssl)
                 else {
                     temp |= (oldWindow[i-idx] << newDiff);
                     window[i] = temp;
-                    temp = oldWindow[i-idx] >> (DTLS_WORD_BITS - newDiff);
+                    temp = oldWindow[i-idx] >> (DTLS_WORD_BITS - newDiff - 1);
                 }
             }
         }