files missing from track

Good evening, I finished a project yesterday and I'm sure I saved; I listened to the finished product a few times after saving. Today I went on soundtrap on my phone and adjusted the volume of one of my tracks, but when I saved a notification popped up that said some files couldn't be retrieved, and to check back again later. It's been about 5 hours and the parts of a track are still missing, can you please help me restore them?