Review implemented

src/reducers/FiatRateReducer.js

@@ -14,10 +14,21 @@ export const initialState: Array<Fiat> = [];
 
 const update = (state: Array<Fiat>, action: FiatRateAction): Array<Fiat> => {
     const newState: Array<Fiat> = [...state];
+    let exists: ?Fiat = newState.find(f => f.network === action.network);
+    const { network, rate } = action;
+
+    if (exists) {
+        exists = {
+            network,
+            value: rate,
+        };
+    } else {
         newState.push({
-        network: action.network,
-        value: action.rate.current_price.usd,
+            network,
+            value: rate,
         });
+    }
+
     return newState;
 };
 

src/services/CoingeckoService.js

@@ -33,7 +33,7 @@ const loadRateAction = (): AsyncAction => async (dispatch: Dispatch, getState: G
                 dispatch({
                     type: RATE_UPDATE,
                     network: response.symbol,
-                    rate: response.market_data,
+                    rate: response.market_data.current_price.usd,
                 });
             }
         });