let's encrytp some issues failed to obtain certificate

I've got an error when obtaining SSL certificate, I try to understand the log but it no luck, don't understand which part went wrong, please help

below is the error message

Parsing account key... Parsing CSR... Registering account... Already registered! Verifying signwareexpress.com... Wrote file to /home/signwareexpress/public_html/.well-known/acme-challenge/2MX6pGOtaoXL-us8YXtOiTZNvGv79L4Zy2JPgPQKf14, but couldn't download http://signwareexpress.com/.well-known/acme-challenge/2MX6pGOtaoXL-us8YX... Traceback (most recent call last): File "/usr/share/webmin/webmin/acme_tiny.py", line 202, in main(sys.argv[1:]) File "/usr/share/webmin/webmin/acme_tiny.py", line 198, in main signed_crt = get_crt(args.account_key, args.csr, args.acme_dir, log=LOGGER, CA=args.ca) File "/usr/share/webmin/webmin/acme_tiny.py", line 153, in get_crt domain, challenge_status)) ValueError: signwareexpress.com challenge did not pass: {u'status': u'invalid', u'validationRecord': [{u'addressesResolved': [u'45.79.139.34', u'2600:3c03::f03c:91ff:fee0:7085'], u'url': u'https://signwareexpress.com/.well-known/acme-challenge/2MX6pGOtaoXL-us8Y...', u'hostname': u'signwareexpress.com', u'addressesTried': [], u'addressUsed': u'45.79.139.34', u'port': u'443'}, {u'addressesResolved': [u'45.79.139.34', u'2600:3c03::f03c:91ff:fee0:7085'], u'url': u'http://signwareexpress.com/.well-known/acme-challenge/2MX6pGOtaoXL-us8YX...', u'hostname': u'signwareexpress.com', u'addressesTried': [], u'addressUsed': u'2600:3c03::f03c:91ff:fee0:7085', u'port': u'80'}], u'keyAuthorization': u'2MX6pGOtaoXL-us8YXtOiTZNvGv79L4Zy2JPgPQKf14.B97r49jPq6p0h4ivv6NE-cy8AaDEU2uJPRygb8EdHnY', u'uri': u'https://acme-v01.api.letsencrypt.org/acme/challenge/hRce_YJAEQx8WkXZhwlI...', u'token': u'2MX6pGOtaoXL-us8YXtOiTZNvGv79L4Zy2JPgPQKf14', u'error': {u'status': 400, u'type': u'urn:acme:error:connection', u'detail': u'Fetching https://signwareexpress.com/.well-known/acme-challenge/2MX6pGOtaoXL-us8Y... Error getting validation data'}, u'type': u'http-01'}