Why is my sofa orange after cleaning it?

[Plantaholic7353]

So I have a yellow sofa that was bought secondhand and has been cleaned several times to try and freshen it up. Recently, I cleaned just the seat part and it has turned orange. I can’t remember exactly what I used that time but I have been using the Dr Beckmann’s carpet cleaner & their upholstery cleaner, as well as white vinegar. Any ideas what could have caused this and whether I could either get back the original colour OR treat the whole thing so it is at least all orange? Picture attached of the two different fabric colours. Thanks in advance for any help!!

Dr Beckmanns is bleach. I used it on a carpet stain and it went a light orange. When my carpet cleaner man came he said he can always tell when someone has used it

That looks like it's been bleached.

Thanks for your replies! I thought it might have been but I actually put bleach directly onto the un-discoloured fabric and nothing happened. Is there anything else it could be? Could it be the combination of white vinegar and carpet cleaner somehow?

I’m just struggling to know how to turn the rest of the sofa the same colour, because I’ve used the same product all over but only had the discolouration on the seat 🧐