diff --git a/src/rpc/common/Validators.cpp b/src/rpc/common/Validators.cpp
index 47ea3e413..2597ea61a 100644
--- a/src/rpc/common/Validators.cpp
+++ b/src/rpc/common/Validators.cpp
@@ -258,7 +258,7 @@ CustomValidator CustomValidators::CurrencyIssueValidator =
 CustomValidator CustomValidators::CredentialTypeValidator =
     CustomValidator{[](boost::json::value const& value, std::string_view key) -> MaybeError {
         if (not value.is_string())
-            return Error{Status{RippledError::rpcINVALID_PARAMS, std::string(key) + " NotString"}};
+            return Error{Status{ClioError::rpcMALFORMED_AUTHORIZED_CREDENTIALS, std::string(key) + " NotString"}};
 
         auto const& credTypeHex = ripple::strViewUnHex(value.as_string());
         if (!credTypeHex.has_value())
@@ -302,14 +302,18 @@ CustomValidator CustomValidators::AuthorizeCredentialValidator =
             auto const& obj = credObj.as_object();
 
             if (!obj.contains("issuer"))
-                return Error{Status{ClioError::rpcMALFORMED_REQUEST, "Field 'Issuer' is required but missing."}};
+                return Error{
+                    Status{ClioError::rpcMALFORMED_AUTHORIZED_CREDENTIALS, "Field 'Issuer' is required but missing."}
+                };
 
-            if (auto const err = IssuerValidator.verify(credObj, "issuer"); !err)
-                return err;
+            // don't want to change issuer error message to be about credentials
+            if (!IssuerValidator.verify(credObj, "issuer"))
+                return Error{Status{ClioError::rpcMALFORMED_AUTHORIZED_CREDENTIALS, "issuer NotString"}};
 
             if (!obj.contains("credential_type")) {
-                return Error{Status{ClioError::rpcMALFORMED_REQUEST, "Field 'CredentialType' is required but missing."}
-                };
+                return Error{Status{
+                    ClioError::rpcMALFORMED_AUTHORIZED_CREDENTIALS, "Field 'CredentialType' is required but missing."
+                }};
             }
 
             if (auto const err = CredentialTypeValidator.verify(credObj, "credential_type"); !err)
diff --git a/tests/unit/rpc/handlers/LedgerEntryTests.cpp b/tests/unit/rpc/handlers/LedgerEntryTests.cpp
index f8528cef9..82d1396e7 100644
--- a/tests/unit/rpc/handlers/LedgerEntryTests.cpp
+++ b/tests/unit/rpc/handlers/LedgerEntryTests.cpp
@@ -292,7 +292,7 @@ generateTestValuesForParametersTest()
                 ACCOUNT,
                 ACCOUNT2
             ),
-            "malformedRequest",
+            "malformedAuthorizedCredentials",
             "Field 'CredentialType' is required but missing."
         },
 
@@ -312,10 +312,31 @@ generateTestValuesForParametersTest()
                 ACCOUNT,
                 CREDENTIALTYPE
             ),
-            "malformedRequest",
+            "malformedAuthorizedCredentials",
             "Field 'Issuer' is required but missing."
         },
 
+        ParamTestCaseBundle{
+            "DepositPreauthAuthorizeCredentialsIncorrectIssuerType",
+            fmt::format(
+                R"({{
+                    "deposit_preauth": {{
+                        "owner": "{}",
+                        "authorized_credentials": [
+                        {{
+                            "issuer": 123,
+                            "credential_type": "{}"
+                        }}
+                        ]
+                    }}
+                }})",
+                ACCOUNT,
+                CREDENTIALTYPE
+            ),
+            "malformedAuthorizedCredentials",
+            "issuer NotString"
+        },
+
         ParamTestCaseBundle{
             "DepositPreauthAuthorizeCredentialsIncorrectCredentialType",
             fmt::format(
@@ -333,7 +354,7 @@ generateTestValuesForParametersTest()
                 ACCOUNT,
                 ACCOUNT2
             ),
-            "invalidParams",
+            "malformedAuthorizedCredentials",
             "credential_type NotString"
         },