Why is the report on calls not generated?

Question

Asterisk

When trying to generate a report on calls (Reports \ CDR Reports), an empty table of 8 lines appears for any period:
Call Date Recording System CallerID Outbound CallerID DID App Destination Disposition Duration Userfield Account CDR Table CDR Graph
UNKNOWN 00:00
UNKNOWN 00:00
UNKNOWN 00:00
UNKNOWN 00:00
D D "D " "D " D D "D" D D 00:00 D D
S S "S " "S " S S "S" S S 00:00 S S
UNKNOWN 00:00
UNKNOWN 00:00

Answer 1

Problem solved. A knowledgeable person connected remotely to the server and did something there.

Answer 2

There is no data with which to store CDR records.
If it's mysql, check the correct connection in cdr_mysql.conf
If OBDC then cdr_odbc.conf
If something else, then check it.