Bundled items greater than max weight

Hi, I recently sold a bundle of books and have started packing them and I'm told that

Pack your item(s) Use packaging that's sturdy enough to protect the item(s) you're sending. The dimensions of your parcel should not exceed L + 2W + 2H ≤ 108 in, L ≤ 22 in, max weight - 4 lb.

But, my items all together are 5 lb 13 ounces when weighing

I'm using USPS Ground Advantage as the shipper.

Should I cancel the order and tell the buyer to rebuy the items at a bigger size or send the package like that?

What should I do? Any help will be much appreciated!