Does choosing a specific mantra help me clear unresolved energy from the past?

I believe many of my daily emotional reactions are tied to unresolved energy and patterns from the past. These heavy feelings constantly bubble up during quiet time and are difficult to contain. I'm looking for a technique to actively cleanse this deep-seated residue. I want to know if choosing a mantra that is specifically focused on letting go can be more effective than silent breath work for deep processing and clearing this old energy. My name is Vijay and my full birth details are 15th October 1990, 7:15 AM, in Chennai.