Can't Save File On Reason 11

[KNGxRIO]

I'm currently working on a song and I'm trying to save the progress that I've already made but it's not letting me. It's states - Missing File. Unable to save document. The file "Acs06_HH_Stones_125.rx2 [8]" can not be included since it is missing. I started this song a couple of weeks ago and was able to save it all the time up until now. I finished the beat last week and am now working on the vocals so I am super confused as to why something that has nothing to do with the vocals is popping up as a missing file. I didn't remove anything from the beat and I didn't even use that ReCycle Rex File so I am completely lost. Please help.