Autoassembly Duplicates Picking Product

Good day,

I have an issue with system automaticately duplicating the products on the BOM when auto assembly triggered. Its affects my cost and product counts. 

Is this a bug or we have something set up incorrectly? 

To me it looks like system try take product from both bins, but i have no idea why. Support just keep telling me to undo all this orders and it will fix it, but now that i think, i have no idea how many more products affected by this and maybe this is reason why im constantly have issue with my inventory. 

Have anyone had this before and if they had a workaround it?

Rusty

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