Thanks for the advice! That is very nice! How did you update the gallery? Uploaded every photo?
However, I do not think that it is because of my website in my case, since the SimpLy Gallery (https://simplygallery.co/justified/) does not display any blocks on older iPads and iPhones.
The iPhone 6 is definitely an older model, but it is still sold, including in Apple stores.
If someone visits my website with an old iPad or iPhone, they will not receive a message “You cannot see any photos because you are using an operating system that is too old”. He thinks he’s on a website that doesn’t have any photos. Otherwise, photos and other galleries in WordPress are displayed on these devices.