Saving Waveform audio file from iCloud to my iPhone

I create audio files on my PC, save them to Onedrive and then download them to my iphone when I need them. The iphone is running iOS 18.3 and has 150GB storage available; the music file is 56MB. I have consistently been able to do this in the past, but now I get "Error saving media. Please try again in a couple of minutes"

[Re-Titled by Moderator]