I don't know about Fiat Panda earthing blocks, but I can tell you on my 1999 Citroen XM, that in the past I have had to "touch" an earthing bloc on the inside of the front wing to get it to start! The touching and movement obviously re-establishes an earthing contact point on the shell.
After 10 years of sometimes having funny touch and go starting experiences from time to time; and trying over time everything (from jiggling relays, solenoids and fuses and wires to get the starter motor to jump into life........
it just turned out to be an earthing bloc mounting that needed "touching" to wake it up!
Also if your battery is only 2 months old; have all the terminals and contacts been tightened sufficiently? It could it be that one has worked a bit loose after battery replacement?
The symptoms of the bad earthing bloc on my other car were similar to having a flat battery.
As a side note I only ever buy "Varta" batteries now. They outperform other batteries in scientific tests; and my own experience has backed this up.
The worst batteries that I have found for endurance and failures over the years on my cars, have been Bosch.
On our Fiat Panda 1.2 ; it had the quickest battery failure I have ever experienced.
I was driving the car normally for weeks; all lengths of journey. So know the battery was fully charged and working. Everything fine and normal.
I saw my mother start and drive off to go a mile down the road to see a friend. Everything normal. Then 15 mintues later;I got phone call saying the car had broken down/wouldn't start.
Now the time taken was so short; that even if everything electrical was left turned on accidentally; then the car should still start after this brief time period.
This was summertime and daylight; and nothing on the car was left on.
I turned up in my other car. The Fiat gave the classic clicking noise of a flatish battery and would not start. However as the Fiat was flashing up EBD failure etc on the display; I was sure that it was caused by component or computer failure. I towed the car back home.
When I got round to sorting it out, it turned out the battery had
totally failed in one mile of driving. It could not hold any charge even when charged up fully overnight on a car battery charger in the house; it lost all its charge in an hour or two.
There was obviously internal battery failure/shorting out.
With the battery failing in the car this low voltage also caused EDB failure warnings on the display and a high temperature warning. The computer was confused with the low voltage. All these warnings on the display led me to believe at first that it was the car computer at fault & going wrong.
We now realise never to believe the Fiat computer displays and warnings. Luckily the fact that the Panda (mk 2) has an analogue temperature gauge; this means the "computer temperature warning" can be quickly ruled out and ignored.
The battery on the car that failed was the original 7 year old battery. But instead of gradually losing power and cranking capacity over time (how battery failures
normally become apparent); this battery went from hero to zero (from all to nothing) in just a few minutes and one mile of driving.
Since this battery experience, the car computer still gets confused with the engine temperature from time to time; and flashes up warnings even when the car is cold on start up first thing in the morning.
All my years of motoring experiences mean that I, personally, myself only ever buy Varta batteries when my car batteries need replacing. Do read the independent scientific battery testing reports. There can be massive battery variations between brands for the "same" battery. I read the then latest reports two or three years ago now, and now I
only buy the Varta brand of battery.