JPMorgan Chase & Co. Credit Card Complaint

JPMorgan Chase & Co. Credit card department,

Credit line increase/decrease Ohio

Chase freedom credit card approved a credit line increase -/-/- of -. I had the balance at - in -/-/- the following month they decreased my credit line to -. Mind you the purchases were made while the line was at -. Now I 'm over the limit by - and have neg on my credit scores! I did not receive a written letter. Their process to me as a consumer was not done legally. I would like to dispute this company and charges!