diff --git a/CHANGELOG.md b/CHANGELOG.md
index ef75761..92739f9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,8 +4,13 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).All notable changes to this project will be documented in this file.
 
-## [Unreleased](https://github.com/nxtlo/aiobungie/compare/0.2.9...HEAD)
+## [Unreleased](https://github.com/nxtlo/aiobungie/compare/0.2.10...HEAD)
 
+## [0.2.10](https://github.com/nxtlo/aiobungie/compare/0.2.9...0.2.19) - 2023-12-12
+
+## Fixed
+* Fixed `fetch_oauth2_tokens` and `refresh_access_token` raising `BadRequest`.
+* `client_secret` was being logged in the headers when enabling `TRACE` log level.
 
 ## [0.2.9](https://github.com/nxtlo/aiobungie/compare/0.2.8...0.2.9) - 2023-12-1
 
diff --git a/README.md b/README.md
index e48445d..b193ae7 100644
--- a/README.md
+++ b/README.md
@@ -120,7 +120,7 @@ If you have used aiobungie and want to show your work, Feel free to Open a PR in
 * [Fated](https://github.com/nxtlo/Fated/blob/master/core/components/destiny.py): My Discord BOT for testing purposes.
 
 ## Useful Resources
-* Discord Username: `fateq`
+* Discord Username: `vfate`
 * aiobungie Documentation: [Here](https://nxtlo.github.io/aiobungie/).
 * BungieAPI Discord: [Here](https://discord.gg/vP7VC7TKUG)
 * Official Bungie Documentation: [Here](https://bungie-net.github.io/multi/index.html)
diff --git a/aiobungie/error.py b/aiobungie/error.py
index ea51f9a..ed4ec88 100644
--- a/aiobungie/error.py
+++ b/aiobungie/error.py
@@ -438,7 +438,7 @@ def stringify_http_message(headers: collections.Mapping[str, str]) -> str:
         "{ \n"
         + "\n".join(  # noqa: W503
             f"{f'   {key}'}: {value}"
-            if key not in ("Authorization", "X-API-KEY")
+            if key not in ("Authorization", "X-API-KEY", "client_secret", "client_id")
             else f"   {key}: REDACTED_TOKEN"
             for key, value in headers.items()
         )
diff --git a/aiobungie/metadata.py b/aiobungie/metadata.py
index 8635fdc..c17aa7b 100644
--- a/aiobungie/metadata.py
+++ b/aiobungie/metadata.py
@@ -36,7 +36,7 @@
 
 import typing
 
-__version__: typing.Final[str] = "0.2.9"
+__version__: typing.Final[str] = "0.2.10"
 __about__: typing.Final[
     str
 ] = "A statically typed, asynchronous API wrapper for building clients for Bungie's API in Python."
diff --git a/aiobungie/rest.py b/aiobungie/rest.py
index cbb2e83..882d99e 100644
--- a/aiobungie/rest.py
+++ b/aiobungie/rest.py
@@ -172,6 +172,13 @@ def _write_sqlite_bytes(
         pathlib.Path(tmp.name).unlink(missing_ok=True)
 
 
+class _JSONPayload(aiohttp.BytesPayload):
+    def __init__(
+        self, value: typing.Any, dumps: typedefs.Dumps = helpers.dumps
+    ) -> None:
+        super().__init__(dumps(value), content_type=_APP_JSON, encoding="UTF-8")
+
+
 class RequestMethod(str, enums.Enum):
     """HTTP request methods enum."""
 
@@ -473,7 +480,8 @@ async def _request(
         oauth2: bool = False,
         auth: str | None = None,
         unwrapping: typing.Literal["json", "read"] = "json",
-        json: collections.Mapping[str, typing.Any] | str | None = None,
+        json: collections.Mapping[str, typing.Any] | None = None,
+        data: collections.Mapping[str, typing.Any] | None = None,
         params: collections.Mapping[str, typing.Any] | None = None,
         headers: dict[str, typing.Any] | None = None,
     ) -> typedefs.JSONIsh:
@@ -502,18 +510,20 @@ async def _request(
         if self._lock is None:
             self._lock = asyncio.Lock()
 
+        if json:
+            headers["Content-Type"] = _APP_JSON
+
         while True:
             async with (stack := contextlib.AsyncExitStack()):
                 await stack.enter_async_context(self._lock)
 
-                data = self._dumps(json) if isinstance(json, dict) else json
                 # We make the request here.
                 taken_time = time.monotonic()
                 response = await self._session.request(
                     method=method,
                     url=f"{endpoint}/{route}",
                     headers=headers,
-                    data=data,
+                    data=_JSONPayload(json) if json else data,
                     params=params,
                 )
                 response_time = (time.monotonic() - taken_time) * 1_000
@@ -648,13 +658,15 @@ async def fetch_oauth2_tokens(self, code: str, /) -> builders.OAuth2Response:
             "client_secret": self._client_secret,
         }
 
-        data = (
-            f"grant_type=authorization_code&code={code}"
-            f"&client_id={self._client_id}&client_secret={self._client_secret}"
-        )
+        data = {
+            "grant_type": "authorization_code",
+            "code": code,
+            "client_id": self._client_id,
+            "client_secret": self._client_secret,
+        }
 
         response = await self._request(
-            RequestMethod.POST, "", headers=headers, json=data, oauth2=True
+            RequestMethod.POST, "", headers=headers, data=data, oauth2=True
         )
         assert isinstance(response, dict)
         return builders.OAuth2Response.build_response(response)
@@ -672,10 +684,9 @@ async def refresh_access_token(
             "refresh_token": refresh_token,
             "client_id": self._client_id,
             "client_secret": self._client_secret,
-            "Content-Type": "application/x-www-form-urlencoded",
         }
 
-        response = await self._request(RequestMethod.POST, "", json=data, oauth2=True)
+        response = await self._request(RequestMethod.POST, "", data=data, oauth2=True)
         assert isinstance(response, dict)
         return builders.OAuth2Response.build_response(response)
 
diff --git a/pyproject.toml b/pyproject.toml
index ec84bc0..4c1fc3b 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "aiobungie"
-version = "0.2.9"
+version = "0.2.10"
 description = "A Python and Asyncio API wrapper for Bungie's API."
 authors = ["nxtlo <dhmony-99@hotmail.com>"]
 license = "MIT"