Let's say I sold 200 shares of the same stock at a loss on 2 platforms yesterday. 100 on one and 100 on the other. Then today I rebought 100 shares on 1 platform. That platform has now (understandably) caused my sale on its platform to become a wash.
My question is two fold:
Is my sale on the other platform now a wash as well or does a repurchase only disallow the loss from the amount of repurchased shares?
If it is how do I report it that it's a wash and do I add the cost basis of the other shares to my new repurchase as well?