select
    d.id
    ,wt.f
    ,wt.start_work_date
from
    debt as d
    inner join person as per on d.parent_id = per.id
    inner join (
        select
            w.r_debt_id
            ,u.f
            ,w.start_work_date
        from
            work_task w
            left join users u on u.id = w.r_user_id
        where
            u.f = 'Платежи'
    )wt
        on wt.r_debt_id = d.id
    outer apply(
        select
            wtl.r_debt_id
        from
            work_task_log wtl
        where
            wtl.id in (
                select max(id)
                from work_task_log as z
                where z.fd < wt.start_work_date
                group by z.r_debt_id
            ) and wtl.r_debt_id = d.id
        ) x