Welcome @tsip, It sounds like you are still having shoulder pain after having rotator cuff surgery. Here is some information I found on your question.

"They are commonly used to provide pain relief during and after shoulder surgeries. Nerve blocks can be administered either as a single injection or in a continuous fashion through the use of a thin tube called a catheter." --- Outpatient orthopedic shoulder surgery- Your pain relief options: https://www.asra.com/patient-information/types-of-pain/outpatient-orthopedic-shoulder-surgery-your-pain-relief-options

Have you discussed your symptoms with your surgeon or doctor?