In normal times it takes up to 16 weeks or more to process an Amended 1040X return. But these are not normal times. They didn't start opening the mail until June that's been stacking up. Back in March the IRS closed their processing centers and stopped processing mailed tax returns. The IRS says.."We’re experiencing delays in processing paper tax returns due to limited staffing. If you already filed a paper return, we will process it in the order we received it." So you have to keep waiting.
See this IRS page for the latest information
https://www.irs.gov/newsroom/irs-operations-during-covid-19-mission-critical-functions-continue
Then once they open your return, After 3 weeks you can track it here,
https://www.irs.gov/filing/wheres-my-amended-return
