KSP - (In-game) Researched parts cant be bought
So the bug I am having is around purchasing parts after they have been researched.
For 90% of parts the game is working fine, but for a couple it keeps duplicating them in the R&D building.
oO to give you the flow of what happens, in the VAB I want to use a part but it "Requires an entry purchase". So I go to R&D and purchase it. Then I go back to the VAB and it still says "Requires Entry purchase". So I go back to the R&D and the part has duplicated itself with the new duplicate not being purchased. So i purchase the part and go back to the VAB. In the VAB it still says "Requires Entry purchase". Going back again to the R&D I find the part has once again duplicated. I have repeated this 10 times or more and it will seemingly just keep duplicating. Pictures are attached to help and support what I described above.
I am running the game vanilla, no mods installed.
#1 Updated by 4x4cheesecake 4 months ago
Did you start the savegame in a previous version of KSP?
The part you try to buy is the old version of the FL-T400 Fuel Tank which should not be listed in the tech node at all but the game seem to have issues with old parts. There is also an issue with parts moved to another tech node during an update: https://forum.kerbalspaceprogram.com/index.php?/topic/181187-large-engine-plates-absent-in-vab-after-update/