Dear Support Team,It seems to be a widespread issue i am also seeing the same after September security Patch on left side bottom corner very less but visible when brightness is low and in dark mode but not as prominent when brightness is full / direc...
Well I have also update to December security patch but not having the issue mentioned by you can try removing jio Sim & cleaning it's contacts using a soft eraser and insert it back. If that also don't help try to get a new Sim.