Transparent PNG quality issues

[Tan_Tin]

Dear fellow contributors, I am srtuggling to understand technical requirements for transparent PNGs as the official info is too brief and my PNGs were rejected for a couple of times and I don't really understand why. You feeback is deeply appreciated. Thanks!

[Jill_C]

Is this a transparent image? 

[Tan_Tin]

Yes, it is.

[daniellei4510]

Inconsistent edges perhaps?

[jacquelingphoto2017]

Hi @Tan_Tin ,

I'm assuming this is a photograph. The only thing I find is the small clip at the fold corner here.

Otherwise, it would have to be exposure. You probably could add a little more exposure. I believe it is slightly underexposed.

Best wishes

Jacquelin