Quality Issues With the Attached PNG File...

Your picture is out of focus, and you have clipping effects, as shown here:

And there are areas, like here, where I do not understand why they are slightly transparent:

Getting a clean cutout of objects is crucial, if you want to use that object getting pasted in a different scene. One trick to see nearly invisible leftovers from my cutout in Photoshop is, that I use the stroke effect. As if by magic, all the areas where you have worked uncleanly become visible. Tidying up is then extremely easy.

I use a contrast colour, often a full red (in your example, black would be bad) and a stroke size of one to four. I can modify the parameters if needed. You pass over those marks with the masking brush, and the red stains disappear. Easy and fast.

As this picture lacks focus, I would not invest time to fix the errors. The missing focus is irrecoverable.