Welcome to Android Central.
We'll need to have some questions answered and replies from you to really be able to offer you advice.
What phone do you have?
What app or where are you trying to play the audio back?
Have you tried another app or a different way of playing it back?
Is this the first time this has happened?
Zero minutes isn't unusual. This can happen when codecs don't match up exactly, some players cannot read the meta data to extract the time as well as other reasons but typically it is either a fault of the recording, it wasn't added to the data or whatever. I'd be less worried about there being no time shown since it shows a file size that represents 30-40 minutes of audio. While it shows no time, I'm assuming you mean 'remaining' time, remaining does it show a counter for audio playing? If it is showing lapse time counting up, with no audio, is it totally silent, like you don't hear anything. No clicks, ticks, snaps or pops? I'm curious if the audio wasn't muffled or blocked somehow. Where was the mic during the recording?
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