[SR-Users] insert new timestamp value to cdr table

Hi I want to add a new column to acc table.I created a new column in the acc table of type timestamp and named it ring_time. in every call i put the ring time to a $dlg_var like this: $dlg_var(ringtime) = $Ts; then I add a extra column in config like this: modparam("acc", "log_extra", "src_user=$fU;src_domain=$fd;src_ip=$si;" "dst_ouser=$tU;dst_user=$rU;dst_domain=$rd;ring_time=$dlg_var(ringtime)") but when I try to test it always i get: db_mysql [km_dbase.c:122]: db_mysql_submit_query(): driver error on query: Incorrect datetime value: '1591361996' for column `kamailio`.`acc`.`ring_time` at row 1 (1292) Jun 5 17:29:59 kamailio /usr/sbin/kamailio[22901]: ERROR: {2 102 INVITE 105a0f4a3d99a0a5558355e54b43f4e1@192.168.1.121:5060} <core> [db_query.c:244]: db_do_insert_cmd(): error while submitting query Jun 5 17:29:59 kamailio /usr/sbin/kamailio[22901]: ERROR: {2 102 INVITE 105a0f4a3d99a0a5558355e54b43f4e1@192.168.1.121:5060} acc [acc.c:477]: acc_db_request(): failed to insert into database