Which is why I don’t pay any bill online or by phone unless its an emergency! I write and mail a check.
I only have to write one check anymore, and it is hand delivered to the recipient. I would not write a check and entrust it to the US mail system. This week alone, I have had the mail workers deliver wrong packages to my PO Boxes, twice. At least if I am online, I know the site, I get an immediate receipt, and the company can’t say I didn’t pay, because I have proof all over the place.