If your daughter is ND, voices can be very much a part of the presentation. My daughter is autistic and has been hearing voices for a while, it's anxiety and overwhelmed based with her.
We are changing anti-depressant to see if it will help.
Have you got a referral for her to CAHMS or the paediatrician?
The psychiatrist explained it to me as a sensory issue. Most neuro typical have an internal monologue, which we recognise as our thought process. Many neuro diverse brains process information differently, so for example, not being able to think in pictures (or only thinking in pictures). If I said to you "John's Dad", for example, most people would automatically have a picture of the person they knew pop up in their minds. It doesn't always work like that in ND minds. Equally, you might have a thought process that's "I'm dropping the kids at school, I then have to nip to the shops before work, I know I need to finish the report by lunchtime" - that wouldn't necessarily be a series of images for you, but might be for a ND person.
It's the same with the internal monologue. Sometimes intrusive thoughts (so we often have them ourselves "I shouldn't have said that, they'll think I'm an idiot") will present, especially when anxious as someone else saying that.
In my daughter's case, she sometimes hears inanimate objects talking to her. We have had a lot of observations to see whether it's psychosis, but at the moment, the psychiatrist feels that it's probably just extreme anxiety and not coping.
If you don't have any professional help, whilst you're waiting for referrals, try to identify what is causing the most stress, and seeing if you can remove elements of it.
Obviously school and friendships are the two biggies at 7, so see if you can break it down with her - is it the transfer to school (often a big one - changing environments), is it the uncertainty of not knowing the timetable (so ask school to do a now and next or a timetable), is it the fear of being in the playground and being overwhelmed by the noise or not knowing who to play with. Don't do it all at once obviously!
One good way I got helpful responses from my daughter was to come up with something I was struggling with. "I'm really dreading doing these invoices for work, I'm always worried I'll get the numbers wrong. Do you ever feel like that about something?" This approach doesn't work with my son though, so not for everyone.
If you suspect your daughter could be autistic, there are some great books out there.
The easy and simple one to read with her is I'm an aspie girl - here's a link but you can probably get it from the library. It's very few pages so a short read www.amazon.co.uk/Aspie-Girl-autism-spectrum-conditions/dp/184905634X/ref=sr_1_1?hvlocphy=41252&hvnetw=o&keywords=im+an+aspie+girl&hvadid=74079856307036&hvbmt=be&qid=1646300145&hydadcr=28551_2296391&hvdev=c&hvqmt=e&tag=mumsnetforu03-21&hvtargid=kwd-74079786380890%3Aloc-188&adgrpid=1185274432673948&sr=8-1
I read it with my daughter and she said "that's me". It was really helpful to pinpoint the struggles she was having.
Try and make everything as clear as possible in advance - talk through what's going to happen the next day, make sure she's prepared for everything, and see if the school could do social stories or draw and talk with her to help her process the information.
I know it's scary, but it is just a different form of processing information.
Hope some of this ramble helps!