Backup camera for Photography Lumix S5ii

Hi everyone, Lumix photographer here.

I started with the Lumix G7 for videography and soon after realized I wanted to do photography. I upgraded to the Lumix S5ii in December and I love it. The only problems I’ve had are “lens attachment not available” when using my 35-150 (both lens and camera were bought new and haven’t tested other lenses yet) but as soon as I turn the camera off and on again it is fine, and it has only happened once per session. (I’ve cleaned around the lens recently and will see if my next session has the problem) I’ve booked 2 weddings for family friends and I’m starting to get worried about my backup gear. I’m looking to sell my G7 and get a backup camera. I’m wondering what is a good option for me? I’m still in the first year of my photography so I don’t have a huge budget. I’ve been weighing the idea of getting another S5ii or the S5. I know the S5 has worst autofocus, but it is much cheaper so that’s the reason why I’m wondering if it’s really worth it to have 2 s5ii’s or if that’s overkill. I only started the G7 camera in July so it’s a lot of upgrades at once. Thank you in advance :)