The certificate is not trusted by all web browsers

[KangJL]

@Manelas

how can i use the cloudflare ssl in infinity free

This may help

Forcing your wordpress site to use https

Another way will be to use InfinityFree SSL tool to install SSL cert. Then add the custom domain to CloudFlare. Last step will be to change SSL mode to full or full(strict) within CF. No .htaccess modification will be needed. For those who find renewing SSL cert every 3 mths a hassle, get a self -signed cert from https://www.selfsignedcertificate.com/ This method will only work with custom domain.