Best answer
もう一度 mou ichi-do “already/still one time”
To ask someone to do somehing “one more time”:
- (informal) もう一度くれ。Mou ichi-do kure.
- (informal, polite) もう一度してもいい？ Mou ichi-do shite mo ii? (“Is it okay if [I ask] you [to] do it one more time?”)
- (formal) もう一度どうぞ。Mou ichi-do douzo.
- (formal, polite) もう一度してもいいですか。Mou ichi-do shite mo ii desu ka?
- (very formal) もう一度お願いします。Mou ichi-do onegai shimasu.
- (very formal, polite) see two bulletins up
Answer
“One more time” may be “Try again”.
We say “もう一度(or 一回)” ”Mo o ichi-do(or i-kkai)”
“One more time” may be “Please say one more time”.
We say “すみません、もう一度、言って下さい” ”Sumi ma senn, mo-o ichi-do i-tte kuda sai”