Weird premium playtime score difference between 2 days

Hello I explain my problem:

On 11/09/22 I obtained a Premium Playtime Score of 10.75 with a total of 55 visits from premiums member.

On 11/24/22 I got a Premium Playtime Score of 10.8 with a total of 290 visits from Premium members.

If I compare to the average visit duration of my day, on 11/09/22 is 13.80 minutes and on 11/24/22 is 18 minutes.

I am 99% convinced that the total playing time by premium members is much higher on 11/24 than on 11/09 but the Playtime score is almost the same.

Could you explain this difference to me? Do you have this kind of problem? I find that quite frustrating. Thank you very much (i’m french sorry if my english is not very great)