What is a service based dissertation?

Can you give some examples as well? Thanks.

I have a personal writer who saved me with writing my dissertation. I think he could help you out w this too. Lmk if you're still in need of such a service, I could share w you his contact details.

Can you give some examples of a service based dissertation as well, like topic ideas? Thanks.

Without any context of what you mean it's basically impossible for anyone to advise.
It would be helpful if you linked to exactly where it's labelled a "service based dissertation".

"Complete a dissertation that creates impact - You’ll complete a service-based dissertation project, informing practice through research."

Again, there isn't much context here. What subject area you're studying would probably guide that considerably.
Since it specifically mentions "practice" it probably implies the dissertation is to be somehow conducted in the process of and based on some kind of placement or similar on the programme, or linked to e.g. creative practice. Again, this will vary wildly depending on what the actual area is.
It's probably also reasonable to discuss with the programme coordinator/director of studies if it's unclear anyway.

sorry, I should have given more context, I just finished my undergrad, will be graduating in June. And I was looking at course information for possible master degrees to study. I came across this term and was confused so I asked it here hoping someone would know.

The course name is 'childhood development and wellbeing in practice'. What I replied to your other post, is what it says as part of the course information on the MMU website. Thanks.

I'm guessing since it's an "in practice" degree that you'll either have integrated placements or are expected to be working in a related area while doing the degree, and then I imagine they expect the dissertation to be based on that work?
It does note in the dissertation module description for that programme that all dissertations are expected to include primary data collection which probably supports that interpretation.
As you're not on the programme already it's probably worth reaching out to them to understand what is involved in that (and/or seeing if you can attend an open day - as you may have the chance to ask current students about it!).