iCloud Issue for Voice Memos

A voice memo I created was 18 minutes and it showed so, and then suddenly, a few minutes later, it showed as only 2 seconds long, across all my Apple devices (I have 4 devices). The Apple support advisor I was on Chat with could not explain why this happened and how to get my original file back. The advisor informed me that while I have voice memos activated in my iCloud backup, they do not back up and only sync between Apple devices that I use with my iCloud ID. While chatting with her, I noticed other voice memos reduced in size. Hence, I had to take the situation under my control, disconnect from wifi/data, and back up my voice memos manually. However, I cannot find those voice memos that were reduced in size before I did this. She told me to contact a third-party service provider, which I find very uncomfortable because (1) I pay almost £20 a month for 250BG of iCloud storage and back-up to Apple so that I do not lose my data, (2) I chose to have Apple devices & OS and not Microsoft because I do not want my data accessible by third-party providers. I hope Apple contacts me, gives me a solution, and ensures that voice memos and other apps that we sync with our iCloud account are backed up because the advisor made me believe that they are not. If anyone knows a solution, please let me know. I am willing to try it.