Efficacy and Safety of CD19/CD20 CAR/TRuC-T in Relapsed/Refractory B-Cell Lymphoma

1. Study Title: A Study on the Efficacy and safety of CD19/CD20 CAR/TRuC-T in Relapsed/Refractory B-Cell Lymphoma 2. Study Objectives: Primary Objective: To evaluate the safety of CD19/CD20 CAR/TRuC-T cell therapy in patients with relapsed/refractory B-cell lymphoma. Secondary Objective: To evaluate the efficacy of CD19/CD20 CAR/TRuC-T cell therapy in patients with relapsed/refractory B-cell lymphoma. Exploratory Objective: To assess in vivo expansion and persistence of infused CD19/CD20 CAR/TRuC-T cells. 3. Participant Intervention: Participants will receive lymphodepleting chemotherapy (FC regimen: Fludarabine + Cyclophosphamide) on Days -5, -4, and -3 relative to the planned CD19/CD20 CAR/TRuC-T cell infusion. The CAR/TRuC-T cell infusion will be administered 72 hours after the completion of the FC chemotherapy.