PNC Bank Bank Account Or Service Complaint

PNC Bank Bank account or service department,

Checking account Deposits and withdrawals Michigan

My business has declined in the last two months, - of my business accounts have been overdrawn for a couple weeks I spoke to a banker over the phone and explained my situation to them and gave them a date when I can bring the account current. My other business account with them had only $1400.00 they withdrew money out of that account and put the money in the account that is negative, now both accounts are negative. All the money the business had was pulled out. Not only will I start being charged for the account that was already but now I have - accounts negative. I understand they can offset an account but how can they offset the account and bring both accounts in the negative?