Use the grapple ability you just obtained on the ceiling above you, the tutorial with the button input is just above you (for controller that's Y or triangle)
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It may seem obvious, but in the heat of the moment even the most obvious solution can be missed. And honestly yours isn't the first comment I've had about not realising this mechanic straight away.
It just shows how you should never assume your players will figure things out without clear instruction. Also that corner needs a complete redesign, its just a disaster waiting to happen.