I dropped two different iPhone XS's both have 4013 error!

Hello,

I dropped a refurbished (gently used I'm good condition) with a good screen protector and one of those extended battery "protection" case which made the phone a lot heavier. It didn't break the screen physically but shortly afterwards it went into the green screen boot loop which eventually led to me having to spend another $220 to buy another one.

I bought another one (iPhone XS) and used the same case was very careful with it but I did drop it and it went into a similar boot loop but without a green screen.

I attempted the repair with the older phone but lost some screws already.

Also the new phone I was able to FINALLY get out of the boot loop but pressing the right button will usually put it right into boot loop again...

Any advice on the right button?

Should I go with the repair on the newer phone and try and reseat all the connections?

Is there a step by step tear down of the xs?

I bought a screen replacement from Amazon and just want some advice on the earpiece thing as I don't care that much about face ID.

Thanks.