This might be tricky depending on how your test case and dataset are being used.
Here are a couple of approaches that you might try. No guarantee which, if any of these approaches, will work.
1) If you can move your dataset into a subprocess, the dataset should reset each time the subprocess is invoked. Unclear if your test case would support this or not.
2) You could try to add a script step to reset the dataset. For example:
import com.itko.lisa.test.DataSet;
import.com.itko.lisa.test.DataSetManager;
// find the dataset by sending instance of testExec and string name of your dataset to findDataset
DataSet ds = DataSetManager.findDataset(testExec, "<name of your ds here>");
// send a reset command to the dataset
ds.reset();
return true;
As stated, no guarantees either approach will work.
Maybe someone else will chime in with additional alternatives.