Per data from Yahoo Finance today was the 6th highest volume day since the merger. Below are the top six days for share volume with their estimated dollar volume:
3/19/2021 - 64,414,800 ($150,730,632)
3/22/2021 - 43,000,600 ($130,076,815)
3/12/2021 - 12,932,600 ($24,313,288)
3/18/2021 - 9,309,700 ($16,990,202)
3/23/2021 - 8,917,300 ($22,739,115)
8/20/2021 - 6,108,146 ($13,652,880)