GRB 221216A: Nanshan/NEXT optical upper limits

We observed the field of GRB 221216A detected by Swift (Dichiara et al., GCN 33067) using the NEXT-0.6m telescope located at Nanshan, Xinjiang, China. We obtained a series of frames in the Sloan r-band and z-band, starting at 11:23:09 UT on 2022-12-16, i.e., 109s after the BAT trigger. No optical source is detected in our stacked images at the XRT position (Dichiara et al., GCN 33067), with upper limits as follows: T_mid-T0 (min) Filter Upper limit(3-sigma) 14.26 r >17.5 14.90 z >16.5 calibrated with the nearby SkyMapper field and not corrected for Galactic extinction.