Error in Surv(time, status) : Time variable is not numeric

[vzsmitj]

I'm trying to perform the survival analysis but I keep getting the following error message:

Error in Surv(time, status) : Time variable is not numeric

I have a survival df which says the values in the two columns are both numeric so I'm not sure what the issue is!

str(BCON_os)
'data.frame': 234 obs. of 2 variables:
$ os.time : num 27 57.4 77.5 32.5 89.6 16 4.5 13.8 18.6 73.5 ...
$ os.status: num 1 1 0 1 0 1 1 1 1 1 ...
imsig_survival (exp = BCON_expr, cli = BCON_os, r = 0.6, time = 'os.time', status= 'os.status')
Error in Surv(time, status) : Time variable is not numeric

Please can anyone advise?