Did I miss something?

Last month I went to my pain management physician for my monthly med check. I have terrible lumbar spine pain, cervical spine pain, and I just had a reverse shoulder surgery. Everything was fine and they sent in my script to the pharmacy that is recommended by my medicare plan. The pharmacy called later, and told me that they are limiting the quantity of one of my pain medications. I called the pain management office and they said that's fine,the remainder will be called in when you run out of your current prescription. I thought that is fine. A few days prior to me running out I called the pain management office for the remainder of my script. I recieved a call back from the office manager, and she stated that they could not refill the remainder of the script. She said all major pharmacy's are limiting the quantity of opioids allowed per month permanently. The pharmacy's are limiting the amount of opioids do to the opioid crisis. Once again, did I miss something? I have had this same prescription for six years, and I comply strictly with my pain management contract. She did say I need to find a local pharmacy to fill the prescription, and forget the big box store pharmacy's.
I am confused. What actually happened that the chain and big box store pharmacy's started limiting the quantity of my medication? Does anyone have an answer to this?