Mahindra Thar doesn't crank until the battery is disconnected and reconnected - repeat issue, no fix

There's an issue with the Mahindra that not cranking. Developed three months back after two years of ownership.
What happens?
~ the engine won't crank after having parked it.
When does it happen?
~ once a month for the last three months.
Solution? (spelt a very EMBARRASSING temporary fix.)
~ disconnect the negative battery terminal with a number 10 spanner / pana and reattach it after 5 seconds. Problem solved.
Troubleshooting?
~ took out all relevant fuses and relays and put them back. Including the immobilizer which is the usual suspect.
~ the car is obviously reading the crank since the AC blower goes off while cranking.
~ the battery is not the problem else the car wouldn't crank on resetting the battery terminal. Also, the instrument cluster would restart if the battery were low.
Contacted MnM care / customer support?
~ yes, three times, via email with video proof. To no avail. The best they managed was to give me a choked DPF after cranking the car about 15 times, the only time I've had a DPF issue in years. The problem was never the battery, and yet, with great forethought, the battery was tested.