I am new to sql and right now I learn joins. the problem is in my table cars_equipment it shows my 4 times the same name. why ?

   SELECT
    c.id,
    c.model,
    c.description,
    c.environment,
    c.equipment,
    c.ps,
    c.tuv,
    c.cover,
    c.brand,
    c.price,
    c.engine,
    c.fuel,
    c.firstregistration,
    c.km,
    c.color,
    c.video,
    c.type,
    c.show,
    c.sit_place,
    array_agg(ci.image) as images,
    array_agg(ce.name) as equipments
    FROM cars c

    LEFT JOIN cars_images ci
    ON ci.car_id = c.id

    LEFT JOIN cars_equipment ce
    ON ce.car_id = c.id

   WHERE c.show IS TRUE AND c.id = $1 

   GROUP BY c.id, ce.id

   LIMIT 1;

what I am doing wrong ?

if I remove group by ce.id then it shows my 20x null values and 4x times the same value