show your parenting code is your player

[mental merlin]

it's a rigidbody

private void OnCollisionEnter(Collision collision)
{
if (collision.gameObject.CompareTag("Player"))
{
collision.gameObject.transform.SetParent(transform);
}
}

private void OnCollisionExit(Collision collision)
{
    if (collision.gameObject.CompareTag("Player"))
    {
        collision.gameObject.transform.SetParent(null);
    }

}

[quiet shuttle]

Make an addition box collider, set it to trigger the same size as your platform

change the code to be OnTriggerEnter

[mental merlin]

Alright lemme try

[quiet shuttle]

iirc there might be one more step

[mental merlin]

The new box collider should be on the parent ?

[quiet shuttle]

look my screeenshots

just clone the platform, put only boxcollider to trigger. You can disable mesh renderer. I have mine to green for debugging

put the script on the trigger

something like this

parent would be the platform MovingPlatform parent

[mental merlin]

okay let me get clear myself , so I have a parent object MovingPLatformParent a normal gameObject in which there is this moving platform child object with box collider and the script

[mental merlin]

I didn't got your point here

[quiet shuttle]

huh did you look at my example ?

it's exactly what u need to do

except mine character is Character Controller instead of rigidbody

it should work the same

[mental merlin]

Yes I saw it so you have a moving Platform parent in which there is a collider as well as script for the parent correct ?

[quiet shuttle]

the parent does nothing but hold the object

and has an animator for moving up and down

you ofc wanna parent player to the parent that holds it all instead of the platform graphics

[mental merlin]

Ohkayy Now i got a clear idea

[mental merlin]

right !!

[quiet shuttle]

exactly, however ur moving the platform should be done to the parent

think the parent as the MainObject

that holds the whole system

if you need more lmk

[mental merlin]

Yeah sure mate ! , anyways thanks for the help

[quiet shuttle]

you got it working ?

[mental merlin]

Uh no actually it's late night here so I stopped working as I was tired I'll try it tomorrow ! , Good night :)