Q: uploading photos to iCloud sharing album

i have attempted to upload around 500 photos to a shared album on iCloud however it has only uploaded 76 and when i try again to add more it says sharing however many photos (i have tried with smaller amounts at first)  it says sharing 2 (lets say) photos at the top right hand corner for a long period of time but then the photos are never actually added to the album... extremely infuriating