diff --git a/models/api/finstitutions/payments/request.py b/models/api/finstitutions/payments/request.py
index c35f4a0..c88d86d 100644
--- a/models/api/finstitutions/payments/request.py
+++ b/models/api/finstitutions/payments/request.py
@@ -113,7 +113,7 @@ class PaymentRequestMetadata(BaseModel):
     idClient: int = Field(frozen = True)
     inAccount: int = Field(frozen = True)
     reference: str | None = Field(frozen = True, default = None, validate_default = True)
-    againstReference: dict | None = Field(frozen = True, default = None, validate_default = True)
+    againstReference: str | dict | None = Field(frozen = True, default = None, validate_default = True)
     documentUrl: str | None = Field(frozen = False, default = None, validate_default = True)
 
     # ┏┓    ┏•