trouble with ios15.7.4 update

so every time i try to do an software update (ios15.7.4) it literally will download the update but once i go to install it almost immediately something pops up saying something about failed to verify because i’m no longer connected to internet and it’s not true i’m always on wifi, the same wifi i’ve done nearly all the previous updates while connected to.. i don’t get why it’s all of sudden not working so weird i do have an iphone7 so possibly that has something to do with it? help pls lol ty