[2020] Weapon reconfiguration

Hello, I have a problem with the reconfiguration of my exotic "Mantis" I modified the weapon three times two days ago, but since I can not redo any more modification on tear while obviously I have all the resources .
When I am at the start of the repackaging or I choose the amre I have the following message.
"all the manufacturing conditions are not met"
I'm lost...
thank you in advance