。
I'm really at my wit's end.
Literal
Truly hand-raising [is-だ].
お手上げ is an idiom meaning 'at wit's end / stumped / total surrender,' literally 'hand-raising' — the gesture of holding one's hands up in surrender. The お- prefix is an aesthetic politeness marker that has become fossilized into the idiom; it does not mark honorific speech here. Subject omitted.