Hi @MichaelP
Are your photos stored in the phones storage or Sd Card.
If Sd Card then its might be corrupt in someway.
Try removing the Sd Card and wipe the contacts and turn the phone back On.
Daily Driver > Samsung Galaxy s²³ Ultra 512Gb in Phantom Black.
The advice I offer is my own and does not represent Samsung’s position.
I'm here to help. " This is the way. "
