Xiaomi is cautioning Mi A3 owners not to download a global firmware update because of "a serious bug" that prevents dual-SIM customers from utilizing both slots. The warning comes after an Indian user came into trouble with his OTA.

Dakshit Shah tweeted yesterday that his phone could not make or receive calls after installing the 1.4GB package. From a brief clip of his device's boot sequence, it appears that the image may be intended for single-SIM A3 phones on Mexican carrier Telcel. We also infer that his system language has been changed to Spanish.

In its warning to the Mi Community forums, the company told users to watch out for v11.0.3.0.QFQMXTC — indeed, destined for Telcel. It's not clear if the proper global image, v11.0.3.0.QFQMIXM, has rolled out to any units. The quest now: find a fix before customers' last bits of patience run out.

Every Mi A-series phone has received at least one update that broke critical features.