Cache doesnt doesnt "discriminate" between args

[TC-CPHI]

Hello,

Im trying to implement an in memory cache which looks at the following function. The goal is to have a cache for the same types of fromdate and todate queries that are called with the function. Yet when implementing an in memory cache as follows it always returns the same query results despite the args of the function changing to new fromdate and todate's. I've tried with custom key builders and various approaches but it seems that the cache itself is flawed?

@asynccontextmanager
async def lifespan(app: FastAPI):
    FastAPICache.init(InMemoryBackend())
    yield

app = FastAPI(lifespan=lifespan)


@app.get("/InitInt")
@cache(expire=3600)
async def InitializeInternal(api_key_fetch: str = Depends(header_scheme), fromdate : Annotated[str, Header()] = None, todate : Annotated[str, Header()] = None, offset : Annotated[int, Header()] = None):

#SOME SQL CODE