iPhone 5c won't download photos

My old iPhone 5c screen stopped working so I got another one and got the photos transferred over to the new one. some of them downloaded but the others just show up as a white box and when I tap on them it just says "loading.." and at the bottom of my albums it says "downloading.." I am almost always connected to wifi and I have plenty of space on my phone. I don't know what the problem is and I have tried everything. Does anyone know what could be happening pr how I could fix it?