Steps to reproduce:
1) Have a landing pad on a planet
2) Try to upgrade with a new one of higher quality by placing a ghost
What should happen:
Landing pad is upgraded to a higher quality pad
What happens instead:
Game shows error that only 1 landing pad is allowed on planet
[2.0.23] Cargo landing pad can't be upgraded with a higher-quality one
Re: [2.0.23] Cargo landing pad can't be upgraded with a higher-quality one
Are you trying to place it on the same location or a different one?
Re: [2.0.23] Cargo landing pad can't be upgraded with a higher-quality one
https://forums.factorio.com/viewtopic.php?p=644054 recommends using an upgrade planner to upgrade quality of an entity.