iPhone 8 Charging Circuit - What is the problem?

Hello!

I have an iPhone 8 came in as won’t power on, no charge.

Customer said that she was using her phone as normal, and suddenly the phone has turned off, and does not powered on since.

I have took out the motherboard of the phone for visual inspection under Microscope. I have seen a big solder ball which came out under U3300

I have replaced the chip. Now the phone powers on but if I plug in the USB charger cable it shows that the phone is charging but actually no Amperage drawn. So the phone is not actually charging.

I have tested with known Google charging port and known good batteries as well but the problem remains.

I checked Q3200 and 3201 are not missing. I have desoldered them to make sure they are not loose.

Anyone can help to diagnose this problem please.