Water in Dynamic Island

IMMEDIATELY backup your iPhone. Then power it off and put in a warm dry play for a few days. DO NOT put it in rice, that can cause more damage.

More importantly, be prepared to purchase a new iPhone. iPhone is not now, nor has it EVER been waterproof and if the phone is damaged, it cannot be repaired.

NEVER swim with or submerge an iPhone in water. Warranty doesn't cover liquid damage.

No iPhone is waterproof.

Apple official directions are not to submerge your phone in water.

By swimming with your phone, you have voided your warranty and damaged your phone.

About splash, water, and dust resistance of iPhone 7 and later - Apple Support

To prevent liquid damage, avoid:

• Swimming or bathing with your iPhone
• Exposing your iPhone to pressurized water or high velocity water, such as when showering, water skiing, wake boarding, surfing, jet skiing, and so on
• Using your iPhone in a sauna or steam room
• Intentionally submerging your iPhone in water
• Operating your iPhone outside the suggested temperature ranges or in extremely humid conditions
• Dropping your iPhone or subjecting it to other impacts
• Disassembling your iPhone, including removing screws