Manually issued certificates can't renew automatically.
If you recall to how you issued that certificate, you would have created some TXT records and placed them in your DNS.
This procedure has to be repeated every time your certificate needs to be renewed. Certbot cannot do this without input from you, which is why a cronjob won't work.
At the end of the day, if you want automatically renewing wildcard certificates, you're going to need to pick a DNS hosting and ACME client combination that supports this workflow.
Certbot doesn't support "Unoeuro" (your DNS host), but acme.sh is an alternative that does. Please read here: dnsapi · acmesh-official/acme.sh Wiki · GitHub