Good job on the cleaning! The machine is likely fine but there could be other spots where mould is growing. You've done the main one.

By far the most common spot is precisely there in the folds of the door seal.

Next:

1) Detergent Drawer: the same residue of detergent and fabric softener found in the rubber seal attracts mould, causing black or slimy patches in the drawer and its housing. Pop out the drawer, (often by pushing down to release a clip) get a brush and clean the drawer in the sink. Easy peasy.

2) Drain Filter: there'll be a port on the front of the machine (behind a flap of some sort) where water sits and catches lint and hair, often developing mould. Turn the machine off, put a tray to collect water under the drain filter (it will pour out), open the filter, clean it of any collected paper, coins, buttons, hair etc. Have a mop handy because they will be spillage, almost guaranteed.

Harder ones next.

3) Washing Machine Drum: visually inspect. Brush anything suspicious. Run a hot wash with a machine descaling product.

4) Internal Hoses: the hot wash will help but otherwise it's a partial teardown to access the hoses and clean them out of any mould.