Lost Gold After Wins
I have lost gold drop similar to some other posts in the bug report forum. Today the game has not given the gold for three to five wins.
Thank you for looking into the issue.
For this issue, please submit at: https://mtgarena-support.wizards.com/hc/en-us/requests/new and select 'General Questions'.
On December 17th, the same thing happened to me as it did to you.
I've been keeping track of the gold I've earned each day, and today I only earned 550 gold compared to the day before, even though I should have completed 15 wins and 500 gold quests.