Iām not certain but I think the error is because there are characters after the @ sign. The name [email protected] should probably be _sip._tls.@ here @ is your apex domain.
To add a SRV record in the Cloudflare dashboard I entered one as follows:
(YOUR_MISSING_NAME is just your domain name and can be left blank)
Also, are you using/adding any other Office 365 services? if not, make sure you have the following CNAME.
lyncdiscover is an alias of webdir.online.lync.com