fell in the water salt and I don't know how to fix

Hi,

You may as well tell your mother as the chances of fixing the phone may be slim

As you know water and electronics and electricity are not a good mix.

The impurities in water, especially salt water causes corrosion and provides circuit paths for the electricity which were not in the phone's operating design and could damage the components.

First do not turn on your phone and then you need to remove the battery as soon as possible from the phone to minimize further damage.

Then you need to dis-assemble the rest of the phone and clean all the affected parts using Isopropyl Alcohol 90%+ (available at electronics parts stores) to remove all traces of corrosion and water. Do not use "rubbing alcohol" as in some cases this is only 70% IPA or less, can contain scents and is not as effective. If you do check the label to verify the amount of IPA

Here is a link that describes the process.

Electronics Water Damage

You may have to replace the battery as it is very hard to recover a battery from salt water damage.

As always with electronics, especially surface mounted PCBs be gentle when handling and especially when brushing away the corrosion. You do not want to remove any components from the board.

Hopefully after you have done all this the phone might possibly work correctly again.

Here is a link to a video that shows how to replace the screen in the phone. It is useful as it shows how to open the phone so that access to the internal components is possible.

If this process seems too daunting, take your phone to a reputable, professional phone repair service, experienced in liquid damage repair and ask for a quote for a repair. If you decide to do this, do it sooner than later.