regexp on responsebody

Hi all

//does not work
.check(regex("""“number”:"(\d{8})"""").saveAs(“myPhoneNumber”))

//works but need to verify length
.check(jsonPath("$.number").saveAs(“myPhoneNumber”))

body=
{“number”:“999999999”,“countryCode”:“47”}

I need to verify that the phonenumber is 8digits, but I’m unable to make any regex match, only jsonpath.
Is regex() only on header?

Thanks

Found it:
.check(regex("""“number”:"(\S*)"""").saveAs(“myPhoneNumber”)), do not know why \d{8} do not work