Role has Reduced

Hi All,

I've been in my role for almost 4 years, however I can't help but feel it's surplus to requirements. Virtually the entire year goes by with no interaction with my boss except at the end of the year when I get my obligatory bad review, although this year my rating improved to "consistently strong" but my boss said not to read anything into an improved rating. I work in a different location from my team and despite making myself available for more work it either doesn't come or I'm overlooked when I complete it. My boss said a very odd line to me when she said "we're not sure what you do". Is this grounds for asking to be laid off or would this make things worse? The environment is quite toxic as it is and I don't want them taking the lay off request as an excuse to fire me.