回复：我的贷款利率被锁定在４.８５％ ３０年，

This response might be too late for you, hope you already got what you wanted.

Did your loan officer agree on re-lock without fee before closing? Is it possible for re-lock with a fee? at least that would give you an option. Bring in anothe mortgage and try for your bargin power, be prepared for fee too.