Wildcard let's encrypt certificate with virtualmin

When you request a let's encrypt wildcard certificate with virtualmin you may have an error like this:

Saving debug log to /var/log/letsencrypt/letsencrypt.log
Plugins selected: Authenticator manual, Installer None
Renewing an existing certificate
Performing the following challenges:
dns-01 challenge for example.com
Waiting for verification...
Cleaning up challenges
Failed authorization procedure. example.com (dns-01): urn:ietf:params:acme:error:dns :: DNS problem: NXDOMAIN looking up TXT for _acme-challenge.example.com - check that a DNS record exists for this domain
IMPORTANT NOTES:
 - The following errors were reported by the server:
   Domain: example.com
   Type:   None
   Detail: DNS problem: NXDOMAIN looking up TXT for
   _acme-challenge.example.com - check that a DNS record exists
   for this domai

For the example I use OVH domain provider.

Example : Domain : example.com
1. Add NS record to your personel server
example.com     NS - Name Server     ns.example.com.
2. On OVH -> WebCloud ->Domain->DNS Server, Add new name server
ns.example.com  -> YOUR_SERVER_IP
3. Wait for propagation

Check with for example:
1
- add test A record to your Name srver
test     A - IPv4 Address     8.8.8.8
- add test TXT record to your Name srver
_test     TXT - Text     TESTOK

2. Check with
ping test.example.com
nslookup -q=txt _test.example.com

If you can see the TESTOK and 8.8.8.8, The DNS Configuration is correct

3. Then request the certificate