413 error request too large

Hi ,
I’ve tried several times to create a private course but everytime I try to upload an audio file in the lingq import page, the loading bar reach 100% and the system stucks showing the error above " 413 request too large".
Is there a limit regarding the size of an audio one can import or am i doing something wrong?
The file I 'm trying to load has a size of 300mb and the following specs: mp3 costant bitrate 64kbps 44100Khz

How long is the audio? The system does not allow to upload audios which are longer than 60 minutes. I guess you need to split the audio into some smaller parts.

Hi tagliuzz,
64kbps and 44100Khz are fine, but the size of your audio file is too big. Maximum supported size is 20MB.