No, because you misunderstand what deflation is. It is a drop in inflation of 0.6% only - which is actually still above zero.
A drop from 13.7% to 13.1% is a lower inflation rate, but it is still way above a zero percent inflation rate (i.e., 0%) and is definitely not a negative rate.
For example, a zero percent interest on your bank account is written as 0%, not as a reduction in the interest rate from 13.7% to 13.1%.
Interestingly, official data for food prices contradicts your claims: "Cost of food in Russia increased 14.20 percent in September of 2022 over the same month in the previous year. source: Federal State Statistics Service" (
https://tradingeconomics.com/russia/food-inflation).