Cannot log in to Facebook on iMac using Chrome

I have an older imac desktop computer an iphone and ipad . No problem accessing facebook on phone and ipad . using chrome . Yesterday on the imac when i tried to access facebook i cannot log in getting a message Check your notifications on another device and confirm its me . I confirm and still no access . Anyone know the problem . I can access facebook on the imac using Safari browser no problem . I changed my password still nothing . i cleared cache and data and cookies nothing helped