How to use par() to combine four ggpar-objects into one in R?

I know that there are countless of questions on how to combine plots. However, I have not found a solution that works for my request.

Please, find a Data sample below.

I have four plots, which all are produced by the same script (but loaded from different data). I cannot get it to work with par() when using ggpar for my ggsurvplot.

pfs <- survfit(Surv(resp.time, response) ~ 1, data=w)
os <- survfit(Surv(Follow.up.death, Death) ~ 1, data=w)

fit <- list(PFS = pfs, OS = os)
j <- ggsurvplot(fit, data = w, combine = TRUE, 
           risk.table = TRUE,                  
           conf.int = TRUE,                    
           conf.int.style = "ribbon",            
           censor = TRUE,                     
           tables.theme = theme,
           ggtheme = theme,
           xlim = c(0,24),
           ylim = c(0.4,1),
           legend.labs=c("PFS (All)","OS (All)"),
           alpha=0.8,
           size=0.7,
           conf.int.alpha=c(0.1),
           xlab="Months",
           break.x.by = 3,
           surv.scale="percent",
           palette = c("#1C73C2","red"))

ggpar(j, font.x = c(11, "bold", "black"), font.y = c(11, "bold", "black"),font.tickslab = c(11), font.legend = c(12))

So, I produce four different ggpar-plots and I would like the presented graphically like the demonstrated below

I have tried

ggarrange(aa, bb, cc, dd, 
          labels = c("A", "B", "C", "D"),
          ncol = 2, nrow = 2)

When aa <- ggpar()1, bb <- ggpar()2, cc <- ggpar()3 and dd <- ggpar()4

But I receive this warning:

Argument needs to be of class "ggplot", "gtable", "grob", "recordedplot", or a function that plots to an R graphicsdevice when called, but is a ggsurvplotggsurvlist

Here is a sample of my data

# Data sample
w <- structure(list(resp.time = c(18, 2, 13, 17, 22, 2, 6, 5, 12, 
8, 3, 2, 1, 21, 2, 43, 4, 2, 4, 5, 0.1, 137, 4, 87, 17, 24, 72, 
19, 14, 83, 68, 56, 57, 18, 14, NA, NA, NA, NA, NA, NA, NA, NA, 
NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, 
NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, 15.6, 8.9, 15, 16.4, 
7.7, 75.5, 3, 54.8, 22.2, 12, 14.3, 6, 12, 21.8, 6, 3, 12, 3, 
6, 3, 3, 12, 9.7, 3, 3, 12, 3, 6, 3, 6, 4, 50, 21, 30, 5, 11, 
12, 4, 18, 6, NA, 3), response = c(0L, 1L, 0L, 0L, 0L, 1L, 1L, 
1L, 0L, 0L, 0L, 1L, 1L, 0L, 1L, 0L, 1L, 1L, 1L, 0L, 1L, 0L, 1L, 
0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, NA, NA, NA, NA, 
NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, 
NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, 0L, 0L, 
0L, 0L, 0L, 0L, 1L, 0L, 0L, 1L, 0L, 1L, 1L, 0L, 1L, 1L, 1L, 1L, 
1L, 1L, 1L, 1L, 0L, 1L, 1L, 1L, 1L, 1L, 1L, 0L, 1L, 0L, 0L, 0L, 
0L, 0L, 0L, 1L, 0L, 1L, NA, 1L), Death = c(0L, 1L, 1L, 0L, 0L, 
1L, 0L, 0L, 0L, 1L, 1L, 1L, 0L, 0L, 1L, 0L, 0L, 0L, 0L, 0L, 1L, 
0L, 1L, 0L, 0L, 0L, 0L, 1L, 0L, 0L, 0L, 0L, 1L, 1L, 1L, 0L, 0L, 
0L, 0L, 0L, 0L, 1L, 0L, 0L, 1L, 0L, 0L, 0L, 0L, 0L, 1L, 0L, 0L, 
0L, 0L, 0L, 0L, 0L, 0L, 0L, 1L, 0L, 0L, 1L, 0L, 1L, 0L, 1L, 1L, 
1L, 1L, 0L, 0L, 1L, 0L, 1L, 0L, 0L, 1L, 0L, 1L, 0L, 1L, 1L, 1L, 
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 0L, 1L, 1L, 1L, 0L, 1L, 0L, 
0L, 0L, 0L, 0L, 0L, 0L, 1L, 0L, NA, 1L), Follow.up.death = c(18, 
2, 14, 17, 31, 4, 20, 15, 12, 19, 10, 17, 27, 22, 3, 43, 24, 
14, 13, 5, 12, 137, 22, 87, 48, 24, 72, 32, 14, 83, 68, 56, 57, 
18, 16, 70, 1.9, 69.2, 126.3, 41.6, 17.9, 1.3, 87.4, 4.4, 137.4, 
17.5, 95.8, 65.2, 14.8, 98.5, 16.6, 74.9, 10.3, 43.4, 32.5, 4.8, 
7.3, 107.8, 6.8, 18.3, 33, 25.2, 49.2, 15.9, 1.2, 42.7, 1, 9, 
1.8, 15.6, 8.9, 15, 16.4, 7.7, 75.5, 12.2, 54.8, 22.2, 9.7, 14.3, 
5.2, 64.5, 21.8, 0.2, 7.3, 18.7, 5.1, 17.3, 27.4, 16, 24.2, 9.7, 
8.2, 5.7, 41.8, 10.6, 22.8, 4.8, 6, 4, 50, 21, 30, 5, 11, 12, 
4, 18, 6, NA, 3)), class = "data.frame", row.names = c(NA, -111L
))

Thank you in advance.