what ro do to return unreadable script handwriting?

When you are in the batch, above the toobox on the left is "Batch", click on it, when the menu opens, click "Return Batch". Any indexing that you have completed will be saved, this will return the batch, so it will be available for another indexer to check out.

You can also return the batch "My Batches", under My Batches is a "Manage" button. When you click it, it puts boxes next to each batch, click the box of the batch(s) you want to return, then on the right you will a "Return Selected Batches" button, click it and it will return the batch.