diff --git a/src/main/kotlin/org/ethereum/lists/tokens/TokenChecker.kt b/src/main/kotlin/org/ethereum/lists/tokens/TokenChecker.kt
index 477f8c645..4bf92a443 100644
--- a/src/main/kotlin/org/ethereum/lists/tokens/TokenChecker.kt
+++ b/src/main/kotlin/org/ethereum/lists/tokens/TokenChecker.kt
@@ -64,11 +64,10 @@ fun getRPC(chainId: ChainId): EthereumRPC? {
 
 suspend fun checkTokenFile(file: File, onChainCheck: Boolean = false, chainId: ChainId? = null) {
 
-    file.reader().use { reader ->
-        Klaxon().parseJsonObject(reader).checkFields(mandatoryFields, optionalFields)
+    val jsonObject = file.reader().use { reader ->
+        Klaxon().parseJsonObject(reader) ?: throw InvalidJSON("Failed to parse token json")
     }
-
-    val jsonObject = Klaxon().parseJsonObject(file.reader())
+    jsonObject.checkFields(mandatoryFields, optionalFields)
     val address = Address(jsonObject["address"] as String)
     val addressEIP1191 = if (jsonObject["address_eip1191"] != null) Address(jsonObject["address_eip1191"] as String) else null
 
@@ -193,4 +192,4 @@ fun JsonObject.checkFields(mandatoryFields: List<String>, optionalFields: List<S
         throw IllegalArgumentException("$this contains unknown $unknownFields")
     }
 
-}
\ No newline at end of file
+}