Integration has different results with different read list order(same data)

[Futurecityrecords]

Hello!

I finished the Vignettes, want to perform the integration.
I followed the [Introduction to scRNA-seq integration], when I put the command
list <- c(readRDS("A"),readRDS("B")), it would be a result. When I change the order to
list <- c(readRDS("B"),readRDS("A")), it would be another result, clusters number is changed dramatically.
How to solve this problem?
Thank you so much.