Slow query

Hello, I have a very slow query,

if I remove the

WHERE active is null

Its work great (there is an index on that field of course)

Query:

SELECT data_gis.id, ex_data.title, ex_data.description, ex_data.ex_text,  
    ST_Y(ST_Transform(way, 4326)) as lat, ST_X(ST_Transform(way, 4326)) as lon, active 
FROM ex_data join data_gis 
    on ex_data.data_gis_id = data_gis.id 
WHERE 
    active is null 
    and ST_DWithin(ST_Transform(ST_SetSrid(ST_Point(51.758783,-1.152665), 4326), 3857), way, 5000.0)  
ORDER BY 
    way <-> ST_Transform(ST_SetSrid(ST_Point(51.758783,-1.152665), 4326), 3857)  
LIMIT 25;

Query plan:

 Limit  (cost=60141.06..60143.98 rows=25 width=269)
   ->  Gather Merge  (cost=60141.06..60175.13 rows=292 width=269)
         Workers Planned: 2
         ->  Sort  (cost=59141.04..59141.40 rows=146 width=269)
               Sort Key: ((data_gis.way <-> '010100....'::geometry))
               ->  Nested Loop  (cost=285.26..59135.79 rows=146 width=269)
                     ->  Parallel Bitmap Heap Scan on ex_data  (cost=284.82..28888.62 rows=10972 width=148)
                           Recheck Cond: (active IS NULL)
                           ->  Bitmap Index Scan on ex_data_org_lang_pkey  (cost=0.00..278.24 rows=26334 width=0)
                                 Index Cond: (org_lang IS NULL)
                     ->  Index Scan using data_gis_pkey on data_gis  (cost=0.44..2.76 rows=1 width=137)
                           Index Cond: (id = ex_data.data_gis_id)
                           Filter: ((way && '010300002......'::geometry) AND ('010100002011.....'::geometry && st_expand(way, '5000'::double precision)) AND _st_dwithin('01010...'::geometry, way, '5000'::double precision))
(13 rows)