Damaged paint on BMW i3

[glennjamin]

Friend of mine has asked me to post this. He's got a BMW i3 went away for a month in camper for a monthon return has got big lump of bird poo on the roof which has eaten into the plastic roof. Any idea of how to sort it out. Removed mess and has risen and appears burnt ?

[paintman]

Probably the acid of the bird poo has etched into the roof.
In the absence of any photos best course would be to have a bodyshop look at it & advise.