how copy from one stringstream object to another in C++?

I have std::stringstream object ss1. Now, I would like to create another copy from this one.

I try this:

std::stringstream ss2 = ss1;

or:

std::stringstream ss2(ss1)

neither works

The error message is like this:

std::ios::basic_ios(const std::ios &) is not accessible from bsl::basic_stringstream, bsl::allocator>::basic_stringstream(const bsl::basic_stringstream, bsl::allocator>&).