Positive FRER but negative clear blue digital?

Kelly • Married since May 2017💜Baby girl born 6/5/19💞TTC since June 2020 for baby two☀️11/20🌈👼 BFP #2 1/5/21🥰

10DPO and have lines on FRER, IC tests and a positive FRER digital test (says yes), but the clear blue digital just said not pregnant much to my shock and horror. What is this all about?