Melee weapon puzzle pieces went missing when trying to build the weapon

Product: Battlefield 1
Platform:PC
Summarize your bug When I finally collected the fifth puzzle piece for the French butcher knife unlockable melee weapon from the operations battlepacks, I went to build the weapon. I've built almost all other melee weapons already, and for those the process went as it should, but this time when I clicked the button, all 5 puzzle pieces disappeared, and the weapon didn't get built. I've exited and re-entered the game several times, also reinstalled it since, even had a look from the companion app, but the weapon is still locked everywhere, with no puzzle pieces showing.
How often does the bug occur? Occasionally (10% - 49%)
Steps: How can we find the bug ourselves? I'm not sure this can be replicated.
What happens when the bug occurs? The weapon doesn't unlock, but the system deducts the 5 puzzle pieces.
Please select your region Europe
In what game mode did the bug occur? Operations
AMD or Nvidia Model Number GTX 980M
Enter RAM memory size in GB 16 GB

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I'd appreciate if there would be a way on Dice's end to correct this error, and grant the unlocked weapon. I've sunk a lot of time into grinding out the operations battlepacks. Thanks in advance!