mysql5.5 sql_thread not running row based relay log

The master and slave are mysql5.5.60 and binlog_format=MIXED;Now it is found that the slave loses some data,But the error log is empty and show slave status status is normal； Parse the master binlog log and slave relay log and find that the lost data still exists, but sql_thread does not apply these logs. These logs are in row based format；what is this caused by？