Understanding transistors....

I don’t know much about transistors but I have one question and that question is… The IRF5305 is behaving differently from the IRF9Z34N, of course, but I ordered the IRF9Z34N and they told me they were out of stock. So they asked me if it was ok to send me the IRF5305…. Well of course not knowing much like I said… I told them ok. I got them here and they are completely different. I’m using these mosfets for led switching. The 5305 u have to apply a ground to the base to turn it on. It remains on until u apply a positive source to the base. Any help ???

How is your circuit wired up?