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Hi !
The free blood flow legendary gem, was not released to me, during the event collection.
Device Type: mobile
Device Model: Samsung
Device Operating System: android
Diablo Immortal App Version: mobile
I am having same issues with it no gem for android users if your account is under a gmail it says nothing is there when you click on it so
Try going to the external website to redeem. Some people are reporting better success. It could take up to an hour before the gem is delivered:
https://shop.battle.net/family/diablo-immortal/items/1953871