Function ***should not be called from a Blueprint from Source

Hi, I have this error message everytime I try to package my game.
It was working fine the last time I tryied to build it and the only this I’ve done between the builds was to change an input mapping in the project settings, I did not opened a blueprint, I did to nothing in the blueprint related to this error

[2017.03.20-20.07.03:765][  0]LogBlueprint:Error: [Compiler W_Inventory] Error Function 'UpdateSelection' called from  Update Selection
Using Interface BP_Inventory_Interface  should not be called from a Blueprint from Source: /Game/Blueprints/InventoryUI/W_Inventory.W_Inventory
[2017.03.20-20.07.03:854][  0]LogBlueprint:Warning: [Compiler W_Inventory] Warning [0057.56] Compile of W_Inventory failed. 1 Fatal Issue(s) 0 Warning(s) [in 149 ms] (/Game/Blueprints/InventoryUI/W_Inventory.W_Inventory)
[2017.03.20-20.07.03:855][  0]LogBlueprint:Warning: [Compiler W_Inventory] Warning [0057.56] Compile of W_Inventory failed. 1 Fatal Issue(s) 1 Warning(s) [in 0 ms] (/Game/Blueprints/InventoryUI/W_Inventory.W_Inventory)
[2017.03.20-20.07.03:856][  0]LogBlueprint:Warning: [Compiler W_Inventory] Warning [0057.56] Compile of W_Inventory failed. 1 Fatal Issue(s) 2 Warning(s) [in 0 ms] (/Game/Blueprints/InventoryUI/W_Inventory.W_Inventory)

I still need help, I can’t build my app anymore…