Found problem on TA-Demisto configuration

Hi All, I'm install splunk on windows. After i'm insert parameter of "Demisto URL/Hostname/IP Address" and "API Key" i'm found error "Encountered the following error while trying to update: Error while posting to url=/servicesNS/nobody/TA-Demisto/demisto/demistocustomendpoint/demistoenv". Then i'm try to run command "curl -ku 'username:password' https://localhost:8089/servicesNS/nobody/TA-Demisto/configs/conf-demistosetup/demistoenv/ -d VALIDATE_SSL=false". But still not work. Please help. Thank you.