"mysql query, group by and then order by most recent grouped with condition" Code Answer

i have added this in the where clause and it seems to be working

where 
'$myid' in ( senderid ) and senderdelete = 0 
or
'$myid' in ( receiverid ) and receiverdelete = 0

full updated code

 $query_messages = mysqli_query($link,"select 
      prequery.*,
      m2.message,
      m2.senderid,
      m2.receiverid,
      m2.senderdelete,
      m2.receiverdelete
   from
      ( select 
              if( m.senderid < m.receiverid, m.senderid, m.receiverid ) as person1,
              if( m.senderid < m.receiverid, m.receiverid, m.senderid ) as person2,
              max( m.messageid ) as lastmessageidperchat,
              max( m.date ) as lastmessagedate
           from 
              messages m
           where 
                   '$myid' in ( senderid) and senderdelete = 0 or '$myid' in ( receiverid) and receiverdelete = 0 

           group by
              person1, 
              person2
           order by 
              m.date asc
           limit 10 ) prequery

         join messages m2
            on prequery.lastmessageidperchat = m2.messageid    order by 
              date desc");
$row_messages = mysqli_fetch_assoc($query_messages);
$totalrows_messages = mysqli_num_rows($query_messages);

By Tillmann Seidel on July 17 2022