To remove the last & sometimes hardest bits, and to go over it entirely to have every little spot removed, I used the fluid print-remover for plastics.
It says "Druck- und Lackentferner" on the label, so it most probably also whipes away (somewhat) of the varnish of the plastic.
But Playmo is not that shiny anyway. And I´ll come back to the topic of getting the shine back further down in the thread.
This product comes in a small bottle. One should use it carefully, because it is probably toxic (though there is no warning on the flask).
So best in a ventilated room (window open) and with a mouth-cover.
Don not inhale the vapour!
And certainly do not drink it, even if you are very thirsty, or when having accidentally swallowed ink before.

Take a clean piece of cloth, and put some drops of the print-reomver on it.
Wipe hard & long enough and everywhere over the (remaing) printing. If necessary, add more drops of the fluid on the piece of cloth.
It might also be a good idea to wear plastic house-hold gloves on your hands when using this product.