One of the languages has posed a huge problem to me since the beginning of this year. Actually, problems started to become apparent in my second year but I brushed them off and carried on as normal
There are so many gaps in your OP, OP -- what was the problem with this language? Was it about your comprehension of it, or about a mismatch of teaching & earning styles, or changes of staff, or what?
As an academic , but not in ML, you've really done the classic head in sand thing. We're used to it. Instead of asking on an anonymouys internet forum (I understand why, really I do, but this is tough love) you need to make an appointment with your Personal Tutor ASAP.
At the places I've taught (all quite competitive) we would never just allow someone to repeat a year or intercalate simply because they hadn't done as well as they wanted to. UNLESS there were other things going on in their lives, which were not caused by their lack of care, work etc, but real obstacles to performing as well as they could. If there have been obstacles (chronic illness, disability, family breakdown, etc etc) then we really do try to help you to deal with them, and try to work out a way of levelling the playing field somewhat. You'll find that there is support.
But I'm surprised you haven't done a year abroad in the country of one of your languages, either working or studying. Is that a possibility you could add now?
Otherwise, I'm afraid my attitude would be that IF the "huge problem" was simply not doing as well as you wanted to (ie 2, ii instead of 2, i marks) AND there were no extenuating circumstances (generally universities call these "mitigation"), then you'd have to suck up the 2, ii. It's not the end of the world. It's an Honours degree and the 2, ii used to be the average expectation. TBH, I really resent the pressure students try to exert by saying "Oh but I need a 2, i" If you need a 2, i do the work. If you have problems see your tutors They have office hours, or email & make an appointment.
So my genuine advice is that
a) today, you need to do a thorough self-reflection on what the "huge problems" are with one of your languages. Be tough with yourself. Once you've done that, think through what you can do to improve your performance. Be constructive, but realistic.
b) tomorrow (not today, it's Sunday) email your Personal Tutor, or your Department's Director of Studies, or the DEpartment's SEnior TUtor, or whoever has been identified to you as the person who can advise you on your overall progress. It's always been standard practice where I've taught that we invite our Personal tutees to see us one-to-one once a term to discuss general progress. The idea is that the relationship develops so that if you hit a bad patch, you can talk to your Personal Tutor about strategies for progress and getting through.
You'll need to state the problem succinctly, and be positive and constructive about how you think you might deal with it, and whether there's support, advice, guidance from the academic staff.
Of course, if there are things outside your own academic performance, now is the time to discuss these. It will be in confidence. If it were with me, I'd be a bit testing at first about why this hasn't been an issue until you realised you might not get the overall degree result you think you "need."
It really is a pity you didn't do something about this in your second year. Just approaching your Finals, it's difficult for even the most caring proactive tutor to help you as much as you think you are gong to need it.
One strategy might be to think about a 1 year Masters at a high prestige/elite/research-led University, as a way of "topping up" a less than stellar undergrad degree. If you really have the talent that your module marks suggest (it's hard for me to know really as I'd need to know the university you're at), then a Masterrs will really give you the opportunity to fly & shine intellectually.
The other thing is to try to remember why you signed up for the degree in the first place. I'm really hoping it was from a love of the study of your languages, a delight in learning, and intellectual curiosity and excitement. If not, and it's about getting the "right" mark to get a job, then a 2, ii is about right ...