votes received
You need to write a terms of condition. When the buyer places an order from you, by doing so the buyer agrees to those terms and conditions

For example

50% reship or no reshipping or full reship for undelivered parcels
Cut off time for shipping
Posted same day or next Etc, etc, etc

Any kind of Signed for is best covers all party’s

But everybody likes a bit of free next day delivery :)

Good luck