For the last 3 months I have been receiving my SS check on the 2nd Monday, instead of the 2nd Wednesday, which is my usual day. Have not received it today, the Monday when I expected, as past 3 months.

Hi. I can' explain why you would have been paid early in the past 3 months, unless your bank credited your Social Security benefit to your account sooner than they should have. In any case, if you were born in the first 10 days of a month and if you're drawing Social Security benefits based on your own work record, then your normal payment date would be on the 2nd Wednesday of each month (https://www.ssa.gov/pubs/EN-05-10031-2021.pdf).

Best, Jerry