Ok, then there is no logistic order line linked to the SV2103150035@@1 service order. At this point, you cannot delete it from the UI but you can look for it in the logistic_order table.
Use the following query to confirm the row exists in this table and is the one that should be removed.
SELECT dm.order_id,
dm.orig_doc_id,
lo.logistic_order_id,
lo.*
FROM logistic_order lo WITH(NOLOCK)
LEFT OUTER JOIN demand_material dm WITH(NOLOCK) ON dm.order_id = lo.logistic_order_id
WHERE dm.order_id IS NULL
AND lo.ldmnd_stat_id = 0
AND lo.logistic_order_id = 'SV2103150035@@1-1'
Please only do this on a copy of your database and validate the results are what you need before applying to production.
If the first column (order_id) is empty, there are no demand_materials though you have a logistic_order that is status Open (ldmnd_stat_id = 0).
Concluding, if you cannot delete IMO, you need to remove the logistic_order_line when there are no material lines.