GRB 190926A: Upper limit from CAHA 2.2m observation

We observed the field of GRB 190926A (Melandri et al. GCN #25848) with the 2.2m telescope at Calar Alto Observatory, Spain. The observation is centered 0.6523 days after the GRB and consisted of 3 x 360 s exposures in the V band for a total exposure time of 1080 s, obtained before technical problems shut down the observation sequence. No new object is detected within the refined XRT error circle (Goad et al. GCN #25850) down to a 3-sigma limit of V(AB) = 21.9 mag, as compared to stars of the GSC 2.3 catalog. This is in agreement with the deep non-detection by OSN (Kann et al., GCN #25856).