diff --git a/freqtrade/data/dataprovider.py b/freqtrade/data/dataprovider.py
index 78d73b07d..b889da17f 100644
--- a/freqtrade/data/dataprovider.py
+++ b/freqtrade/data/dataprovider.py
@@ -167,7 +167,8 @@ class DataProvider:
         producer_name: str = "default"
     ) -> Tuple[bool, int]:
         """
-        Append a candle to the existing external dataframe
+        Append a candle to the existing external dataframe. The incoming dataframe
+        must have at least 1 candle.
 
         :param pair: pair to get the data for
         :param timeframe: Timeframe to get data for
@@ -176,29 +177,32 @@ class DataProvider:
         """
         pair_key = (pair, timeframe, candle_type)
 
-        if (producer_name not in self.__producer_pairs_df) \
-           or (pair_key not in self.__producer_pairs_df[producer_name]):
+        if dataframe.empty:
+            # The incoming dataframe must have at least 1 candle
+            return (False, 0)
+
+        if (producer_name not in self.__producer_pairs_df
+           or pair_key not in self.__producer_pairs_df[producer_name]):
             # We don't have data from this producer yet,
             # or we don't have data for this pair_key
             # return False and 1000 for the full df
             return (False, 1000)
 
-        existing_df, _ = self.__producer_pairs_df[producer_name][pair_key]
+        existing_df, la = self.__producer_pairs_df[producer_name][pair_key]
+
+        # Iterate over any overlapping candles and update the values
+        for idx, candle in dataframe.iterrows():
+            existing_df.iloc[
+                existing_df['date'] == candle['date']
+            ] = candle
+
+        existing_df.reset_index(drop=True, inplace=True)
 
         # CHECK FOR MISSING CANDLES
         timeframe_delta = to_timedelta(timeframe)  # Convert the timeframe to a timedelta for pandas
         local_last = existing_df.iloc[-1]['date']  # We want the last date from our copy of data
         incoming_first = dataframe.iloc[0]['date']  # We want the first date from the incoming data
 
-        # We have received this candle before, update our copy
-        # and return True, 0
-        if local_last == incoming_first:
-            existing_df.iloc[-1] = dataframe.iloc[0]
-            existing_data = (existing_df.reset_index(drop=True), _)
-
-            self.__producer_pairs_df[producer_name][pair_key] = existing_data
-            return (True, 0)
-
         candle_difference = (incoming_first - local_last) / timeframe_delta
 
         # If the difference divided by the timeframe is 1, then this
@@ -228,6 +232,7 @@ class DataProvider:
 
         # Only keep the last 1500 candles in memory
         existing = existing[-1500:] if len(existing) > 1500 else existing
+        existing.reset_index(drop=True, inplace=True)
 
         return existing
 
diff --git a/freqtrade/rpc/external_message_consumer.py b/freqtrade/rpc/external_message_consumer.py
index 743698b24..278f04a8e 100644
--- a/freqtrade/rpc/external_message_consumer.py
+++ b/freqtrade/rpc/external_message_consumer.py
@@ -36,6 +36,9 @@ class Producer(TypedDict):
     ws_token: str
 
 
+FULL_DATAFRAME_THRESHOLD = 100
+
+
 logger = logging.getLogger(__name__)
 
 
@@ -376,8 +379,8 @@ class ExternalMessageConsumer:
 
         logger.debug(f"Received {len(df)} candle(s) for {key}")
 
-        if len(df) >= 999:
-            # This is a full dataframe
+        if len(df) >= FULL_DATAFRAME_THRESHOLD:
+            # This is likely a full dataframe
             # Add the dataframe to the dataprovider
             self._dp._add_external_df(
                 pair,
@@ -388,8 +391,8 @@ class ExternalMessageConsumer:
                 producer_name=producer_name
             )
 
-        elif len(df) < 999:
-            # This is n single candles
+        elif len(df) < FULL_DATAFRAME_THRESHOLD:
+            # This is likely n single candles
             # Have dataprovider append it to
             # the full datafame. If it can't,
             # request the missing candles
@@ -403,9 +406,14 @@ class ExternalMessageConsumer:
             )
 
             if not did_append:
-                logger.debug("Holes in data or no existing df, "
-                             f"requesting {n_missing} candles "
-                             f"for {key} from `{producer_name}`")
+                # We want an overlap in candles incase some data has changed
+                n_missing += 1
+                # Set to None for all candles if we missed a full df's worth of candles
+                n_missing = n_missing if n_missing < FULL_DATAFRAME_THRESHOLD else 1500
+
+                logger.warning("Holes in data or no existing df, "
+                               f"requesting {n_missing} candles "
+                               f"for {key} from `{producer_name}`")
 
                 self.send_producer_request(
                     producer_name,
diff --git a/freqtrade/rpc/rpc.py b/freqtrade/rpc/rpc.py
index 4ebedd6c4..331569de3 100644
--- a/freqtrade/rpc/rpc.py
+++ b/freqtrade/rpc/rpc.py
@@ -1062,7 +1062,7 @@ class RPC:
         self,
         pair: str,
         timeframe: str,
-        limit: Optional[int] = None
+        limit: Optional[int]
     ) -> Tuple[DataFrame, datetime]:
         """
         Get the dataframe and last analyze from the dataprovider
@@ -1083,7 +1083,7 @@ class RPC:
     def _ws_all_analysed_dataframes(
         self,
         pairlist: List[str],
-        limit: Optional[int] = None
+        limit: Optional[int]
     ) -> Generator[Dict[str, Any], None, None]:
         """
         Get the analysed dataframes of each pair in the pairlist.