[1.26m] Cannot merge zones

[chpog]

I've captured an asset of rival regime (oil pump station) but I don't want it as a separate zone, so I assigned a governor and call for zone merging procedure.
I have necessary amount of PP but option is grayed out, unable to perform.
https://ibb.co/LdYxQSb9

P.S.: I still play previous 1.26k2 save game file, but my client (steam) has been updated to 1.26m

[JeanleChauve]

An asset can be delegated, but not merged, it is reserved for cities not too far away.

[chpog]

An asset can be delegated, but not merged, it is reserved for cities not too far away.

OMG! Why? ))
So, I want that zone gone - what would you usually do when conquering an asset (which, apparently, you DON'T want to be a separate zone)?
For this case only think is about changing somewhere in tables that 12 hex range to 400+ to cover most distant maps.

Thanks!

[JeanleChauve]

Without your save, it's hard to give you the best solution. Zip your save and post it here as an attachment.
You can leave the asset in your zone, but you'll get administrative strain.
You can create a new zone in the 6 squares by implanting a colony, but it's a bit complicated to manage the first few times.
If the asset is close to an enemy city (which is probably the case), mothball the asset while waiting to take the city that will manage the asset at that time.
You can also destroy it and recover half of the resources.