I would just ignore it.
Flying to US today - have had numerous emails from BA about how we 'must' use Verifly - but we don't. BA website, app and emails all provide different information. Furthermore, I really object to handing over my information to a 3rd party - Verifly is NOT BA.
(BTW - BA say you have to have Verifly in order to do OLCI, but we managed to without it).