The main problems you will have unfortunately are things you can’t change—lack of garden, size of rooms (assuming the 3rd bedroom is small), attractiveness of building.
The only way to get past these is price or having everything else outweigh the negatives. The kitchen would be the biggest changeable issues tbh—people looking to live there would probably want to update, and a lot of buy to rent landlords are not buying at the moment.
Personally I would spend a little bit on staging, and work in particular on kitchen (to make them look a bit more modern).
Is there a nicer photo of the outside available? Like a lovely autumn or summer one—tbh I think a lot of people won’t look further than this.
Sitting room is lovely but the photo doesn’t look immediately appealing? I think it’s the curtains and the way it had been taken? A big rug on the floor and open curtains would be way nicer—it looks really dark.
Kitchen: curtains need to go. Could you pay a builder to remove the kitchen cupboards, sand and paint? Wouldn’t be that expensive and would make it look a lot better—I think a lot of people see a brown kitchen and assume they’ll have to tear them out.
Lack of third bedroom photo makes you assume box room.
If i were you, I would restage and relaunch with a further discount—do both at the same time, try to hit a new price bracket.