7 month old has stopped using litter tray

[giggly]

Our 7 month kitten who was previously fully litter tray trained has stopped using the tray over the last 1-2 months.
She will pee on the carpet in the hall upstairs and downstairs and on my hard wood floor.
Maybe once a day she will grace the litter tray and then promptly shit on the carpet and tonight she has chosen half way up to her stairs.
I have used a variety of litters but she’s remarkable to prefer wooden pellets, the tray is always clean and I’ve spent a fortune on enzyme sprays.
Nothing is working.
I have two older cats who are like
My house stinks constantly now.
I’ve had cats for 30 years and I’m now out of love with this one and could easily regime her if my kids wouldn’t be distraught.
Any advice gratefully received

How many trays have you got now? For 3 cats you’d need 4 trays.

Is she spayed?

Are they indoor cats?

Folder two cats are outdoor cats and use an outdoor litter tray. They have never peed/ poo on the floor.
She got spayed about 5 weeks ago and I was hoping that this would settle things down.
I have three trays for her one upstairs which she never uses, one in the hall which she will pee in about once a a day and one in the kitchen which again she doesn’t use.
Tonight she done a poo outside my dd bedroom door so that’s a new one😳
I’ve had cats for 30 years and never had this problem.
I’m planning on letting her out for longer this weekend in the hope that this will encourage her to use the tray outdoor which they other two use occasionally, as they prefer a woody but at the back of my garden which I ok with.
I’m honestly at a loss.

Sorry must learn to proof read before posting

I had a kitten who would occasionally pee outside the litter tray. I did two things which seemed to solve it. The first was to keep a close eye on him. If he started scratching the floor or looking like he was about to pee, I would say, 'No' and pick him up and put him in the litter tray. The second thing I did was to move a litter tray to a corner of the kitchen where he kept going to pee. I wasn't somewhere that I particularly wanted to have a litter tray, but it did solve the problem. He doesn't go on the floor anymore. In fact he mostly goes outside these days.

Thanks for your suggestions. We do pick her up if we see her and we have trays in all the places she pees on. Twice tonight it was at the open door between my hall and living room so half on carpet and half on my lovely real wood floor I am going to lift and chuck the hall carpet tomorrow as it is absolutely stinking.

Reading post subjects can be entertaining when you forget there is a pet forum on here, and thought you were talking about a 7 month old baby human
This must be frustrating, have you spoken to your vet to check there isn’t a medical reason? It sounds like you are doing the right things already. Hope you find a solution soon.