There were some sticky areas on our 380 when we first brought it home.
Having not had any experience with sticky PVC in the past
I tried some soapy water first, which didn't work and proved it was probably the material itself rather than anything organic stuck to it.
I wiped it over with Acetone and immediately rinsed it off with plenty of water and a sponge to neutralise the Acetone.
All the stickyness was gone, and the surface appeared sealed.
The Acetone cloth was definitely Red, so something was being removed.
However, Iím in no way suggesting anyone does this, holds me accountable for any consequences, own risk, etc, etc.