diff --git a/models.py b/models.py
index be2a39b..2c9f412 100644
--- a/models.py
+++ b/models.py
@@ -1,12 +1,11 @@
 import json
-from datetime import datetime
-from typing import Optional
+from datetime import datetime, timezone
 
 from fastapi import Query, Request
 from lnbits.helpers import normalize_path
 from lnurl import encode as lnurl_encode
 from lnurl.types import LnurlPayMetadata
-from pydantic import BaseModel
+from pydantic import BaseModel, Field
 
 from .helpers import parse_nostr_private_key
 from .nostr.key import PrivateKey
@@ -26,19 +25,19 @@ class LnurlpSettings(BaseModel):
 
 class CreatePayLinkData(BaseModel):
     description: str
-    wallet: Optional[str] = None
+    wallet: str | None = None
     min: float = Query(1, ge=0.01)
     max: float = Query(1, ge=0.01)
-    currency: str = Query(None)
     comment_chars: int = Query(0, ge=0, le=799)
-    webhook_url: str = Query(None)
-    webhook_headers: str = Query(None)
-    webhook_body: str = Query(None)
-    success_text: str = Query(None)
-    success_url: str = Query(None)
-    fiat_base_multiplier: int = Query(100, ge=1)
-    username: str = Query(None)
-    zaps: Optional[bool] = Query(False)
+    currency: str | None = Query(None)
+    webhook_url: str | None = Query(None)
+    webhook_headers: str | None = Query(None)
+    webhook_body: str | None = Query(None)
+    success_text: str | None = Query(None)
+    success_url: str | None = Query(None)
+    fiat_base_multiplier: int | None = Query(100, ge=1)
+    username: str | None = Query(None)
+    zaps: bool | None = Query(False)
     disposable: bool | None = Query(True)
 
 
@@ -47,22 +46,22 @@ class PayLink(BaseModel):
     wallet: str
     description: str
     min: float
+    max: float
     served_meta: int
     served_pr: int
-    username: Optional[str]
-    zaps: Optional[bool]
-    domain: Optional[str]
-    webhook_url: Optional[str]
-    webhook_headers: Optional[str]
-    webhook_body: Optional[str]
-    success_text: Optional[str]
-    success_url: Optional[str]
-    currency: Optional[str]
     comment_chars: int
-    max: float
-    fiat_base_multiplier: int
-    created_at: datetime
-    updated_at: datetime
+    created_at: datetime = Field(default_factory=lambda: datetime.now(timezone.utc))
+    updated_at: datetime = Field(default_factory=lambda: datetime.now(timezone.utc))
+    username: str | None = None
+    zaps: bool | None = None
+    domain: str | None = None
+    webhook_url: str | None = None
+    webhook_headers: str | None = None
+    webhook_body: str | None = None
+    success_text: str | None = None
+    success_url: str | None = None
+    currency: str | None = None
+    fiat_base_multiplier: int | None = None
 
     disposable: bool
 
@@ -73,7 +72,6 @@ class PayLink(BaseModel):
         if url.netloc.endswith(".onion"):
             # change url string scheme to http
             url_str = url_str.replace("https://", "http://")
-
         return lnurl_encode(url_str)
 
     @property