diff --git a/app/Transformers/TransactionGroupTransformer.php b/app/Transformers/TransactionGroupTransformer.php
index e16b3dd03b..32d9f979e8 100644
--- a/app/Transformers/TransactionGroupTransformer.php
+++ b/app/Transformers/TransactionGroupTransformer.php
@@ -388,7 +388,7 @@ class TransactionGroupTransformer extends AbstractTransformer
         }
 
         // set primary amount to the normal amount if the currency matches.
-        if ($transaction['primary_currency']['id'] ?? null === $transaction['currency_id']) {
+        if (($transaction['primary_currency']['id'] ?? null) === (string) $transaction['currency_id']) {
             $transaction['pc_amount'] = $amount;
         }