Q. Is there anyway I can use credit from 2017 and 2018 to offset 2019?
A. Yes. But not an easy way.
As already suggested, you SHOULD amend your 2017 and 2018 tax returns to claim any additional refund and, recalculate the capital loss carry forward. You must report the capital loss carry forward on each year’s return. You are not allowed to postpone using it or saving it for a more advantageous time, like 2019.
You could file an amended 2019 return, before doing that; but at a minimum, you must recalculate the loss carry forward from 2017 to 2018, then from 2018 to 2019.
2017 to 2018 could be particularly complex. See https://ttlc.intuit.com/community/taxes/discussion/do-i-have-to-use-a-capital-loss-carryforward-even...
The personal exemptions were eliminated, starting in 2018.
