I need help with my bar chewing hamster!

[liza]

Hi! I've super recently (about 2 weeks ago) gotten a hamster called ralsei and I've been having a little bit of trouble, and I need some advice.
I'm 17 and still live with my parents, and I've always been in love with animals, so this year my parents got me a hamster cage for Christmas so that I could get a hamster! I was super happy about this obviously but I've always thought that I wouldn't get a hamster or any other animal until I knew that I would be able to look after it properly and give it everything it needs. I know hamsters need big enclosures with different areas of stimulation and such, and unfortunately, although this cage is labeled as extra large it is not quite what I would've chosen to house a hamster in. My family doesn't have much money so I obviously really appreciate the cage my parents have got but I'm just worried that it's not enough for ralsei, and I really just want him to be happy. The cage is quite tall with lots of levels, ramps and quite alot of base space, and has bars instead of glass.
I got ralsei on boxing day and he is such a lovely Syrian hamster. He was seemingly very young when I got him as he was quite small for a Syrian hamster, and since he has grown a bit. I know he is probably still settling in to his new environment but he is still quite skittish. He is very curious and I absolutely adore him so much. However, he has a terrible bar biting problem.
Despite his cage maybe being too small he has loads of chew toys which he does not touch. In his cage I have put wooden nibble sticks, a dangling wooden and straw thing, lots of thick cardboard, and dangling food sticks, however he is not interested in the slightest! The only thing he really ever wants to do is chew on the bars. I've tried lots of different things like slotting in chew sticks through the bars where he commonly chews or weaving cardboard through the bars to try to get him to stop, but he always either chews the cardboard away or justs starts biting the bars in a different part of his cage.
Ive been trying to keep him stimulated and happy as much as I can but I've had problems with this. He has a sand bath in his cage which he loves so much, and if he's not sleeping or chewing on the bars, he will be in there. He also has a wheel in his cage but never uses it (and it definitely does work). However he really loves running in his ball when it's on its stand, but this doesn't really fit in his cage so he can only go in it for about 20 mins a day. I also have a play pen which I put lots of toys and interactive things in but he just seems set on trying to escape instead of playing.
Im so sorry for such a long message and I'm also really sorry if I have put this in the wrong place or anything. This is my first post on this forum but I am absolutely desperate for help. I really want to help ralsei before he develops any negative behaviours permanently or he damages his teeth, and in general I just want him to be more happy! Unfortunately I don't think I could buy him a new, bigger cage right now because I have absolutely no money, but I am saving up. My house is also very small and I know that a big enclosure just simply couldn't fit. If I had known my parents were going to get me a hamster for Christmas I would've told them not to because I just don't have enough money or space to look after one as best as I could, but I'm so glad to have ralsei in my life and I'm really just trying to find ways to improve his.
Any advice would be so greatly appreciated, and again, I'm sorry if I've put this in the wrong place!!