RecruitingPhase 1Drug trialPhase I Study of Preconditioning Radiation Therapy With IL-15 Transduced TGFBR2 KO CAR.TROP2-engineered Cord Blood-derived NK Cells in Patients With Advanced Head and Neck Cancer (RADIANCE-NK)To find the recommended dose of an investigational therapy called chimeric antigen receptor (CAR).TROP2/interleukin (IL)15-transduced TGFBR2 KO cord blood (CB)-derived natural killer (NK) cells (TROP2 CAR/IL-15 TGFBR2 KO NK cells) that can be given with and without preconditioning radiation therapy in patients with advanced head and neck squamous cell carcinoma.