Backlog ordering vs Sprint ordering

Hello,

I’m using Azure Dev Ops and would like some help please.

When I look at the backlog and put it in a nice order, all my items are correct. But when I bring some items into a sprint and order them, my backlog order is then unordered. 

Our backlog structure is like this:

• Epic A
  • Feature A1
    • PBI Hot
    • PBI Medium
    • PBI Cold
  • Feature A2
    • PBI Hop
    • PBI Skip
    • PBI Jump
• Epic B
  • Feature B1
    • PBI Cat
    • Spike Dog
    • PBI Mouse
  • Feature B2
    • Spike Slide
    • PBI Swing

The problem happens when I have the PBIs and Spikes from both EpIcs in a sprint and I need to order them by priority. 

How can I stop the ordering of a sprint from changing the order in my backlog please?

Any help would be greatly appreciated. 

Garry