I file a joing return and have one dependent. We received a single $4200 Stimulus Payment in March 2021. My wife and I each received Form 6475 saying we received $2100 each which was confusing since we thought ithe payment was only for $1400 each.
Its as though they arrived at the $2100 by splitting my dependent daughter's $1400 into $700 for my wife and me so that we each received $1400 + $700 = $2100.
I think this agrees with what happend to the OP and now makes sense.
