How to integrate MTA Postfix and DLP system?

Question

postfix

Need help implementing the following.
IMPORTANT: everything was done absolutely legally, employees know about monitoring, they signed a bunch of documents, etc.
Initial data:
1) there is a mail server on MTA Postfix - mail.domain.com
2) there are all users of this server - users
3) there is a small list of users - dlp_users , whose mail should go through the DLP system server
4) there is a DLP server, on which needs to forward letters - dlp.domain.com (IP 192.168.1.10)
What needs to be done:
Incoming and outgoing letters from users from the dlp_users list should be sent to the server dlp.domain.com. After that, they are returned back to the mailer and sent to the recipients.
As it was planned to implement:
1) using the smtpd_recipient_restrictions and smtpd_sender_restrictions parameters in main.cf , outgoing and incoming messages are checked against the list of users dlp_users . If the sender or recipient is included in this list, then the letter is redirected to the DLP server
2) the letter is returned from the DLP server and, to eliminate loops in the transport table, is immediately sent to the local port of the built-in content filter - 127.0.0.1:10025
The problem is that it was not possible to eliminate the loops in this way. When sending/receiving a letter for a subscriber from the dlp_users list, the letter starts to go between the mail server and the DLP server until it is discarded due to the excess of the number of hops.
Would setting smtpd_client_restrictions = check_client_access hash:/etc/postfix/dlp_server in main.cf help prevent loops? At the same time, specify in dlp_server : 192.168.1.10 FILTER smtp:127.0.0.1:10025

Excerpts from configs:

main.cf
transport_maps = hash:/etc/postfix/transport
smtpd_recipient_restrictions = check_recipient_access hash:/etc/postfix/dlp_users
smtpd_sender_restrictions = check_sender_access hash:/etc/postfix/dlp_users
dlp_users
[email protected] FILTER smtp:192.168.1.10
[email protected] FILTER smtp:192.168.1.10
[email protected] FILTER smtp:192.168.1.10
transport
192.168.1.10 smtp:[127.0.0.1]:10025