diff --git a/src/fetch/payouts.py b/src/fetch/payouts.py
index c3af462d..bda38fb8 100644
--- a/src/fetch/payouts.py
+++ b/src/fetch/payouts.py
@@ -475,9 +475,13 @@ def construct_payouts(
     batch_rewards_df = batch_rewards_df.drop(
         ["partner_list", "partner_fee_eth"], axis=1
     )
+
+    assert batch_rewards_df["solver"].is_unique, "solver not unique in batch rewards"
+    assert quote_rewards_df["solver"].is_unique, "solver not unique in quote rewards"
     merged_df = pandas.merge(
         quote_rewards_df, batch_rewards_df, on="solver", how="outer"
     ).fillna(0)
+
     service_fee_df = pandas.DataFrame(dune.get_service_fee_status())
     service_fee_df["service_fee"] = [
         datetime.strptime(time_string, "%Y-%m-%d %H:%M:%S.%f %Z") <= dune.period.start
diff --git a/src/pg_client.py b/src/pg_client.py
index caaa4166..b7921dd5 100644
--- a/src/pg_client.py
+++ b/src/pg_client.py
@@ -4,12 +4,15 @@
 
 
 import pandas as pd
-from pandas import DataFrame
+from pandas import DataFrame, Series
 from sqlalchemy import create_engine
 from sqlalchemy.engine import Engine
 
+from src.logger import set_log
 from src.utils.query_file import open_query
 
+log = set_log(__name__)
+
 
 class MultiInstanceDBFetcher:
     """
@@ -57,7 +60,28 @@ def get_solver_rewards(self, start_block: str, end_block: str) -> DataFrame:
                 self.exec_query(query=batch_reward_query_barn, engine=engine)
             )
 
-        return pd.concat(results)
+        results_df = pd.concat(results)
+
+        # warn and merge in case of solvers in both environments
+        if not results_df["solver"].is_unique:
+            log_duplicate_rows(results_df)
+
+            results_df = (
+                results_df.groupby("solver")
+                .agg(
+                    {
+                        "primary_reward_eth": "sum",
+                        "protocol_fee_eth": "sum",
+                        "network_fee_eth": "sum",
+                        # there can be duplicate entries in partner_list now
+                        "partner_list": merge_lists,
+                        "partner_fee_eth": merge_lists,
+                    }
+                )
+                .reset_index()
+            )
+
+        return results_df
 
     def get_quote_rewards(self, start_block: str, end_block: str) -> DataFrame:
         """Returns aggregated solver quote rewards for block range"""
@@ -70,8 +94,17 @@ def get_quote_rewards(self, start_block: str, end_block: str) -> DataFrame:
             self.exec_query(query=quote_reward_query, engine=engine)
             for engine in self.connections
         ]
+        results_df = pd.concat(results)
+
+        # warn and merge in case of solvers in both environments
+        if not results_df["solver"].is_unique:
+            log_duplicate_rows(results_df)
 
-        return pd.concat(results)
+            results_df = (
+                results_df.groupby("solver").agg({"num_quotes": "sum"}).reset_index()
+            )
+
+        return results_df
 
 
 def pg_hex2bytea(hex_address: str) -> str:
@@ -80,3 +113,31 @@ def pg_hex2bytea(hex_address: str) -> str:
     compatible bytea by replacing `0x` with `\\x`.
     """
     return hex_address.replace("0x", "\\x")
+
+
+def log_duplicate_rows(df: DataFrame) -> None:
+    """Log rows with duplicate solvers entries.
+    Printing defaults are changed to show all column entries."""
+    duplicated_entries = df[df["solver"].duplicated(keep=False)]
+    with pd.option_context(
+        "display.max_columns",
+        None,
+        "display.width",
+        None,
+        "display.max_colwidth",
+        None,
+    ):
+        log.warning(
+            f"Solvers found in both environments:\n {duplicated_entries}.\n"
+            "Merging results."
+        )
+
+
+def merge_lists(series: Series) -> list | None:
+    """Merges series containing lists into large list.
+    Returns None if the result would be an empty list."""
+    merged = []
+    for lst in series:
+        if lst is not None:
+            merged.extend(lst)
+    return merged if merged else None