Is it possible to forward this complain to rbi or PMO. ?This will force Sbi to employ experts and investigate it properly.
They will look at it, forward it to the relevant department and give you further instructions on how to follow it up.
It is the ultimate portal for public grievances.
e.g. A few months ago, I wrote to them about the non-acceptance of the RuPay card at some outlets including Dr. Lal's Path Lab and a RGC Melith pharmacy. The complaint was followed up, I received a phone call from Axis bank (regarding their swipe machine) and a reply from pgportal apprising me of the developments and telling me to take up further such matters with the RBI (some link was provided).