Changing x-axis lable and x-axis interval in a ggsurvplot

I would like to make a gg survplot with ggplot in R, I succeeded to make such a survplot but I am wondering how to change the x-axis title and x-axis interval.

Here is the statement I used in R:

sfit <- survfit(Surv(time_until_quit, quits_within_given_interval)~set1, data=DAT1)

ggsurvplot(sfit, conf.int=TRUE, pval=TRUE, risk.table=TRUE,
legend.labs=c("Set1", "Set2"), legend.title="Sets",
title="Curve with information about quitting")

I want to place ‘Time until quitting’ on the x-axis and have a difference of 50 between the intervals.

Thanks for your help in advance!