The option to sort by PI budgets includes budgets that the PI has access to, not just the ones they are PI for. This can include budgets that the PI was given access to but no longer actively uses. In that case, the person who originally authorized the PI for that budget can remove the access in ASTRA.
In some cases, this can also happen when the budget number has been recycled. If the PI used the budget in a previous biennium, and that budget number is reactivated with a different PI and name, because of the records retention policy (three biennia, plus the current biennium) the PI's access will still show that budget. In this case, the PI can check the "active budgets only" box on the budget list, and that budget number will not show up. As the records retention ages out, that budget number will drop off of the PI's access.