Photo upload problem

[Ursa_Major]

I'm having trouble uploading my photos from the Meet into an album. I uploaded them onto my laptop and resized them to 800 x 600 but when I tried to put them into an album it says upload failed or if I try to upload five it says I'm lacking a security token.

I did look further into the photos and despite being resized they still show as being 2.4MB whereas album photos have to be no bigger than 2.5KB so this could be the problem. Any ideas how to get them down to 2.5 KB as I'm totally baffled?