Good morning trusty community!
This morning our acknowledgement flow is giving us grief. I'm using the Acknowledgement Flow that I published in 2023.
It failed yesterday with a “404 Error” and message "File Not Found\\r\\n…" and I don't understand why. During some testing today we changed the letter code to one that worked the day before and now I'm getting a “400 Error” with the message “A file with the same name is currently being saved to this site. Change the filename and try to save again.\\r\\n…” (I confirmed the file does not exist in the folder we are trying to create the file.) I also tried adding a delay before the Create Letter files step and still receive the same error. Below is a snip of the flow.

I'd appreciate if someone could let me know what I'm missing or suggest additional things to test. I'm not sure what could have changed in the last 24 hours to create this error.
Thank you in advance!