Getting a cooking error every time I try to launch a map in game

Summary

Every time I try to launch an island from UEFN in Fortnite to playtest / upload I’m met with an error saying ‘We hit an error while cooking this content’.

I think one thing causing it is copy and pasting assets from one map to another.
For example, I created a structure on a blank map just to have more room to work with yet whenever I copy this structure to the map I want to upload it gives me this error.

If I then remove the copied content over I no longer get the error.

Please select what you are reporting on:

Creative

What Type of Bug are you experiencing?

Assets

Steps to Reproduce

Every time I try to launch my map in game from the UEFN editor I get an error message that’s saying failed to cook content

Expected Result

Same as above. I’m unaware of what’s causing this

Observed Result

Again, I’m unsure of what’s causing this. Sometimes of my maps open in the launcher fine but a lot of other maps fail to launch now

Platform(s)

UEFN

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