Not using litter box

This is long and I tend to ramble but it's the best way to describe his behavior and hopefully someone can give advice! Thanks in advance!
Bofur has stopped using his litter box. I tried changing boxes for him because the smell had soaked in pretty heavily and I know that can be bad for them. I put some of his old newspaper into a new box in the same part of his cage and put hay in it as well hoping to encourage him into going in a new box. Aside from being a brand new box it also has all four sides whereas his other litter box only had three.
Is he just a lazy bum that doesn't want to jump over the edge to get in the box???
Fast forward to the evening and he hasn't used the litter box but has been going in the cage itself. It's not desirable but I could live with that but I'd rather not have him urinating on the fabric on the base of his cage. So I put down piddle pass directly overtop of the fabric in hopes he's smell it thru the pad and do his business there and I put the old litter box back inside the cage. When I woke up this morning he has pottied directly outside of the front of his cage
I've locked him in his cage in hopes to get him to use his box but it has made him very upset-biting bars and chewing cardboard.
Is that the right thing to do? Any thoughts or suggestions are greatly appreciated!

I will reply to your post in a little while but please let him out of his cage.

locking him in his cage won't help. He won't understand why it's happening and all it will do is upset him!

How old is he? Is he neutered?

What on earth is a "piddle pass"???

I would recommend using a large plastic litter tray, which can be washed out and disinfected as necessary. Cardboard just absorbs the pee and becomes smelly - rabbits are inherently clean and don't like a smelly/dirty tray. We tend to use large under bed storage boxes as litter trays. I would line it with newspaper and then fill with hay - don't put any of the wet stuff in it. You could, however, put a few of his poos in the tray.

I've opened his cage back up and he is now investigating his room again. And there is urine in his litter box which was my hope by making him stay in there. Also he didn't bite at his cage for more than a minute before finding his food and cardboard box full of hay.

He is between 2.5 and 3 years old and yes he is neutered.

Babsie said:

I would recommend using a large plastic litter tray, which can be washed out and disinfected as necessary. Cardboard just absorbs the pee and becomes smelly - rabbits are inherently clean and don't like a smelly/dirty tray. We tend to use large under bed storage boxes as litter trays. I would line it with newspaper and then fill with hay - don't put any of the wet stuff in it. You could, however, put a few of his poos in the tray.

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His tray is a plastic cat bin with the front cut out, I use newspaper as a liner as well. I didn't put wet newspaper back in the new tray but I did put the newspaper he had gone on that was changed earlier in the day so it had dried urine and poo on it. I figured he would go in the new pan since it already smelled like him.

A piddle pass is auto corrected piddle pads, the pads you put down to train a puppy where to go or you put under an incontinent elderly person in bed to absorb urine and keep them dry

AmberNikSee said:

His tray is a plastic cat bin with the front cut out, I use newspaper as a liner as well. I didn't put wet newspaper back in the new tray but I did put the newspaper he had gone on that was changed earlier in the day so it had dried urine and poo on it. I figured he would go in the new pan since it already smelled like him.

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Sorry - don't know how I came to think it was a cardboard box! Nevertheless I would line it with clean newspaper and hay - most people change litter trays every day.

AmberNikSee said:

A piddle pass is auto corrected piddle pads, the pads you put down to train a puppy where to go or you put under an incontinent elderly person in bed to absorb urine and keep them dry

Click to expand...

Auto correct!!!

Do you change the actual tray itself??? If that's the case do you have any suggestions how to get him to use the second plastic tray? I change the newspaper every day but he doesn't always hit the middle of the paper and it leaks around the edges.

And a piddle pass was a spelling error that my phone auto corrected, should say piddle pad

Yes, wash out the litter tray every day and use thick layer of fresh newspaper and hay. Is that what you meant?
I love piddle pass, by the way - good old auto-correction.