Radiator Cap - 1.1 bar or 0.9?

[NorthernGirl]

Hello everyone,
I own a 2009 Yaris LE 1,5L hatchback. She was in a accident recently - long story short, everything is fine by now and she runs like nothing happened
But a radiator cap is scratched, so I decide to change it. The thing is, the current one is 0.9 bar. I ordered a OEM new one (and received it already). The seller put in my order a 1.1 cap, instead of 0.9 I chose. They insist the 1.1 cap is the right one, not 0.9
I googled and yes - the most results confirm what the seller said.
But:

- I'm a second owner, bought my car 2 years ago. Right before selling, previous owners did a full inspection at the dealer. There are bunch of recommendations in those inspection's papers - but nothing about radiator cap or cooling system whatsoever.
The dealer just overlooked the "wrong" radiator cap?..

- I've never had any issues with the cooling system since I bought my Yaris. No overheating, nothing is leaking, the ODB shows "all the sensors report no trouble codes", etc. All these 2 years with the 0.9 bar radiator cap

But now I'm confused - which on is the right one? 1.1 or 0.9?

Thanks in advance!