Dishonest seller jumping from site to another, taking payments but sending package, blocking buyer.

[Client:107179912]

Dishonest seller since 2014. Jumping around different sites selling various products. Collecting payment but doesn't send package.
I have information about seller very much. What would be wise to do next?

[Wioletta2701]

@ko_alka @mr_oma @la_nika @nat_not @_HolaOla_  

Potrzebna pomoc. 

[la_nika]

@Client:107179912 can you please send us a message via this form? Please include login of the seller and as many information about this case as you can. Security team will analyze your ticket. 

[Client:107179912]

Today or tomorrow. I have a very strict timeline right now, I will write.