When the nose pads of sunglasses are deformed or fall off, you can follow the steps below to deal with it:

How to deal with deformed nose pads:
First, gently soak the deformed nose pads in hot water to soften the material for easy adjustment.
Then, hold the frame of the glasses with one hand and gently clamp the nose pad bracket with pliers (small and suitable pliers are recommended) with the other hand.
Next, gently move the pliers up or down to adjust the nose pads to the ideal shape and position. Be careful to use moderate force to avoid excessive force that may damage the nose pads or the frame.
Finally, make sure that the nose pads are in good contact with the two planes on the side of the nose and are symmetrical on both sides.
How to deal with fallen nose pads:
If the nose pads fall off, but the nose pad bracket is still intact, you can try to use a special glasses adhesive or double-sided tape to stick the nose pads back in place.
Before using the adhesive, make sure that the contact surface of the nose pads and the nose pad bracket is clean, dry, and free of oil and dust.
Apply an appropriate amount of adhesive to the nose pad bracket, then gently press the nose pad onto the bracket and fix it for a while until the adhesive is completely dry.
Be careful not to use too much adhesive to avoid overflowing onto the frame or lens.
Notes:
When handling deformation or detachment of the nose pad, be careful to avoid damaging the frame or lens.
If you cannot handle it yourself or handle it improperly, it is recommended to go to a professional optical shop or sunglass repair center for repair.
To avoid deformation or detachment of the nose pad, please wear and store the sunglasses correctly, and avoid taking them off with force or dropping them.
Other suggestions:
If the nose pads of sunglasses are often deformed or detached, you can consider replacing them with a more sturdy or suitable type of nose pads.
When buying sunglasses, you can pay attention to choosing products with good quality and reliable brands to reduce the risk of deformation or detachment of the nose pads.