Number within r being wrongly recognized

I have a row of data that is created through ifelse statement of proper data.

 mutate(yrsatrisk = ifelse(!is.na(Age_at_death), as.numeric(Age_at_death), ifelse(!is.na(Age_at_last_update), as.numeric(Age_at_last_update), 0))

However one of the datapoints age_at_last_update = 8 but is then recognized as 80. If i sort the output, that row is set at 80, everything else recognizes it as 80 but one with if else statement that does yrsatrisk - 74 which gives an output of -66

    1060    Male    79  15  15  15  15  15  5   30  30  20
    527 979 Female  79  15  15  15  15  15  5   30  30  20
    26  828 Male    8   15  15  15  15  15  -66 30  30  -51
    150 101 Female  80  15  15  15  15  15  6   30  30  21

which is created by

"0-14atrisk" = ifelse(yrsatrisk > 14, 15, yrsatrisk),
         "15-29atrisk" = ifelse(yrsatrisk > 29, 15, ifelse(yrsatrisk > 14 & yrsatrisk < 30, (as.numeric(yrsatrisk) - 14), 0)),
         "30-44atrisk" = ifelse(yrsatrisk > 44, 15, ifelse(yrsatrisk > 29 & yrsatrisk < 45, (as.numeric(yrsatrisk) - 29), 0)),
         "45-59atrisk" = ifelse(yrsatrisk > 59, 15, ifelse(yrsatrisk > 44 & yrsatrisk < 60, (as.numeric(yrsatrisk) - 44), 0)),
         "60-74atrisk" = ifelse(yrsatrisk > 74, 15, ifelse(yrsatrisk > 59 & yrsatrisk < 75, (as.numeric(yrsatrisk) - 59), 0)),
         "75-85+atrisk" = ifelse(yrsatrisk > 74, (as.numeric(yrsatrisk) - 74) , 0),
         "0-29atrisk" = ifelse(yrsatrisk > 29, 30, yrsatrisk),
         "30-59atrisk" = ifelse(yrsatrisk > 59, 30, ifelse(yrsatrisk > 29 & yrsatrisk < 60, yrsatrisk, 0)),
         "60-85+atrisk" = ifelse(yrsatrisk > 59, (as.numeric(yrsatrisk) - 59), 0))

This is not fixed by forcing yrsatrisk with as.numeric prior to the mutate either. It currently means I have to output the data and edit it and re-input for it to work.

Any ideas?

Dput of couple lines around the 8

structure(list(PID = c(696L, 1060L, 979L, 828L, 101L, 1470L), 
    Gender = c("Female", "Male", "Female", "Male", "Female", 
    "Male"), yrsatrisk = c("79", "79", "79", "8", "80", "80"), 
    `0-14atrisk` = c("15", "15", "15", "15", "15", "15"), `15-29atrisk` =            c(15, 
    15, 15, 15, 15, 15), `30-44atrisk` = c(15, 15, 15, 15, 15, 
    15), `45-59atrisk` = c(15, 15, 15, 15, 15, 15), `60-74atrisk` = c(15, 
    15, 15, 15, 15, 15), `75-85+atrisk` = c(5, 5, 5, -66, 6, 
    6), `0-29atrisk` = c("30", "30", "30", "30", "30", "30"), 
    `30-59atrisk` = c("30", "30", "30", "30", "30", "30"), `60-85+atrisk` = c(20, 
    20, 20, -51, 21, 21)), row.names = 330:335, class = "data.frame")

The expected output should be

   26   828 Male    8   8   0   0   0   0   0   8   0   0