Errors with Shapiro test

I have been trying to perform the Shapiro test on my data with no success recently, I read some topics online which hasn't appeared to help me. The first command I wrote is:

shapiro.test(as.numeric(recup$Temps == "med"))

Which gave me the error:

all 'x' values are identical

Afterwards, I wrote this second command

shapiro.test(recup[recup$Temps == "med"])

Which gave me the error:

is.numeric(x) is not TRUE

Does anyone have any suggestion or can offer their own experience on how to write the correct command, essentially helping me to fix the errors in console that I am encountering.

Could you add information about what you are looking to learn about this character variable?

(recup$Temps == "med") will return TRUE or FALSE.

You are asking if the values of the Temps variable are equal to "med". Converting TRUE and FALSE to numeric will return 1 and 0.

The first error message means that all the values are "med", so all ones, or none of the values are "med", so all zeros.