I would not punish her for it, she is still only four, and has had a lot of change in her young life. It could be a control issue, it could be a medical issue, or she simply could have had a set back and is having accidents....these are not her fault and she should not be punished for them. I wouldn't even have her clean them up...she is still learning being punished for learning is not a good idea. I have a bio son who is four who, while potty trained at almost two, still has accidents on occasion during the night.
They learn much faster if you make a big deal about how proud you are of them when they get it right, instead of getting upset when they get it wrong. If they become stressed about the issue things are only going to get worse!
Now my adopted stepson, when he was about 10 began having some bathroom issues. We ruled out medical reasons and went through the whole nine yards with him. At that age, after being potty trained for so long (years) and THEN suddenly not wiping, we had him go in and clean up the mess when we found it. But honestly, if we just cleaned it up without saying anything the behavior disappeared much faster. He did it when he was highly stressed over something, and us getting upset and having him clean it up, or talking with him about it, made him stress more, which meant more messes to clean up. There was also the gratification for him that he was making us upset, he was controlling our emotions....once we took the reaction out of the equation....the behavior stopped.
His chore in time became to simply clean the bathroom once a month, and he soon learned that if he controlled his behavior he didn't have much to clean up! She will come around in time, but for now, as others have stated, I would just back off, and when it is time to start again, focus on the positive, and not the mistakes.
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