Santander Bank US Bank Account Or Service Complaint

Santander Bank US Bank account or service department,

Other bank product/service Account opening, closing, or management Massachusetts

My APY on my money market account with Santander changed from 1.25 on my -/-/- statement to 1.10 on my -/-/- statement to .75 on my -/-/- statement. I received no notice or notification about the change in my APY nor authorized the change with Santander or agreed to it. This is highly concerning to me as this is a violation of Banking regulations and warrants a complaint. I did try reaching out to Santander customer support and they gave me no written excuse. Instead they told me to call a customer support number which I did and sat on hold for - minutes and could not hold any longer. I think it is ridiculous that the Bank could not respond in writing. I believe this Bank is treating its customers Unfair and are being deceptive about their business with its customers. I would greatly appreciate the CFPB and the regulator of Santander to perform an exam of this Bank and identify all its control breakdowns and deceptive acts and other potential regulatory violations.