Guess, lacking disk setup for that material. Hard to tell without details.
disk setup? its an ssd. I've exported the footage before but this video is twice as long
What are the files that are eating the disk space?
Are they temporary files you thought you redirected elsewhere? Are they the export itself that you thought you redirected elsewhere?
In other words, if we don't know what the files are that are cluttering your SSD, how can we answer?
Is it possible that you don't have a reasonable limit on your paging file?