PTR in cloudflare

Good day. I want to consult on PTR records.
Upon request, our provider turned on the Cloudflare name server at home and registered the reverse domain that we need on its name servers.
It is about 82.179.84.14 and name servers ns.runnet.ru
This ptr record is also registered in the Cloudflare, but does not give the proper result.
There is an assumption that the problem may lie in the fact that we use the free version of the account on Cloudflare.
Do I need to buy a paid version?

PTRs can only be set by the IP owner. This is not Cloudflare in this case.

% Information related to '82.179.0.0/16AS3267'

route:          82.179.0.0/16
descr:          RUNNet
descr:          Russian Federal University Network
origin:         AS3267
mnt-by:         INFR-MNT
mnt-routes:     INFR-MNT
created:        2018-08-01T15:39:25Z
last-modified:  2018-08-01T15:39:25Z
source:         RIPE # Filtered

Addition of a PTR zone on Cloudflare is currently only available for Enterprise customers.

What is the minimum tariff needed for this feature?

For a single IP, you would be much better served simply having the network operator manage it and set the value. It is currently set to:

dig -x 82.179.84.14 +short
mail.stankin.ru.

Our provider placed a PTR record on its name servers, but this is not enough.
By the way, I noticed one bug. If you delete and add a PTR record to the Cloudflare, then for some time the record will actually exist and the result of dig at 1.1.1.1 and 8.8.8.8

But still. What tariff do we need?

Why would this not be enough?

You would need to be on an Enterprise plan which would be silly to simply manage a single PTR record. However you are welcome to contact the sales team to discuss pricing if you insist. https://www.Cloudflare.com/plans/enterprise/contact/

Будут ли наши письма попадать в спам, если на Cloudflare отсутствует PTR запись?

I don’t have PTR records for my website, but I use proper SPF, DKIM, and DMARC records in DNS and my email is delivered successfully.