Product: Checking or savings account

I have been with the bank that is now called Truist for over 20 years with a personal checking account and for the last XXXX  years with XXXX business accounts as well. I have never had an issue with overdraft fees until the bank merged and became Truist. I am an attorney and have my own business. 
For the last several months I have paid approximately {$700.00} in overdraft fees in my business account a a couple XXXX dollars in overdraft fees from my personal account. I did get {$72.00} worth of overdraft fees credited from my personal account and my account changed to XXXX that has a {$100.00} buffer to prevent overdrafts. However, no account is available on the business side and all fees were denied credit in my business account when I called to ask for the refund. 
I use XXXX with a bank register and mobile banking to watch my account closely. When I check my accounts at night prior to going to bed, my accounts will be in the positive with nothing pending negative. My available balance shows that I have enough funds to cover any pending charges if there are any. However, by morning my account somehow rolls into the negative and a {$36.00} overdraft charge is added to my account. Upon reviewing the account, my transactions can change the dates that they are posted, pending. and cleared on the online banking website and app. For example, a charge may XXXX day show that it cleared on the XXXX and the next day show it actually cleared on the XXXX before the funds were in the account which would then result in overdraft fees. The dates of my transactions change from day to day and my available balance changes along with it. It is as if the transactions are manipulated in the bank system until they will incur an overdraft fee. 
I have alerts to let me know thru the bank if my account is low or about to overdraft. XXXX day I received an alert at XXXX that a transaction had just overdrafted my account. Then at XXXX prior to the back opening my account incurred overdraft fees. The night prior to this all items showed in the positive. No new items posted, they just moved around until a fee was assessed. 
Another time I wrote a check for {$75.00} on the XXXX when I had {$89.00} in the bank. I gave the check to my friend who was the recipient after XXXX on the XXXX, so he was unable to deposit it until the next day. I also deposited another {$72.00} in my account to cover an additional charge of {$71.00} on my debit card. There was money for both charges but somehow I still got an overdraft fee for the check which now showed that it cleared on the XXXX. This still doesn't make sense because there was {$89.00} to cover the {$75.00} check and the {$72.00} deposit to cover the {$71.00}. How is there money to cover the charges but I still get an overdraft? How do the dates of the cleared charges change? My available balance shows available funds until something happens overnight and then I get an overdraft. There is no time to add funds or make corrections and no one can explain what's happening. I believe there is some fraudulent manipulation of the funds and the banking system that is allowing the bank to profit from numerous overdraft fees. I for XXXX am sick of their unfair and deceptive practices. I am confident if it is happening to me that it is happening to many others as well.