Erasing disabled iPhone 5s without wifi

Hi! ~

I have an awful memory, and forgot my PIN to my iPhone. I know my Apple ID password, just not the PIN for the physical device. I even went through the whole process of changing my Apple ID password, because I at first, thought I was changing my iPhone's password.

I also tried too many times to enter the PIN, which, of course, disabled the iPhone, so that is lovely. I am fine with erasing the iPhone, as I suppose that is the only option now. However, even though I'm at home with wifi, it won't erase until it is "connected to wifi"! (I saw on the "find my device" thing online that it can't even find the iPhone when it's clearly alive and right next to me, because it won't connect to wifi, for some reason.) What am I supposed to do?

Thanks,

~ RuntySoundGoblin