Office scene. 切れる ('to run out, be exhausted') as a change-of-state verb in the ~ている form marks the resulting state ('is currently out'). ~んですか asks for explanation rather than a yes/no, conveying surprise and inviting confirmation. 仕方ない is the set phrase 'it can't be helped.' The motion-verb purpose pattern 取りに行く = verb-stem + に + 行く ('go in order to fetch') — a core template for expressing movement purpose in Japanese.