אמר לסופר ולעדים לכתוב ולחתום וליתן גט לאשתו וכתבו וחתמו ונתנו לה ונמצא פסול או שכתבוהו ונאבד יכולים לכתוב גט אחר ואם לא נאבד והם מסופקים אם הוא כשר מכמה חומרות שנהגו להחמיר הרי עשו שליחותם וצריך לחזור הבעל לומר להם לכתוב ולחתום: הגה ואם העדים רוצים לכתוב אחר וליתן לה שניהם הרשות בידם ואין צריכים לשאול לבעל (תשובת הרשב"א הובאה בב"י) לכן אם הבעל הולך מהעיר יאמר שהוא נותן להם רשות לכתוב ולחתום גט מאחד עד ק' עד שיהא א' כשר בין בכתיבה בין בחתימה לדעת הרב שבעיר בלי שום פקפוק: הגה ולכל מי שמראה אותו (סדר גיטין) אבל אם הבעל בעיר אין לסמוך על זה ויש לבעל לחזור ולצוות כל פעם לעדים ולסופר (ב"י בשם ר"ת) וכן נוהגין שחוזר ומצוה כמו בראשונה גם מקנה להם הקלף והדיו אם לא נשאר לסופר ממה שהקנה לו בראשונה (כן נמצא בסדר גיטין) וי"א הא דאמרינן עשו עדים וסופר שליחותן צריך לחזור ולצוות היינו דוקא אם כבר נחתם ונפסל אבל אם עדיין לא נחתם יכולין לכתוב אחר ואין הבעל צריך לצוות (ב"י בשם הרשב"ץ) אבל נהגו להחמיר בכל ענין:

If he said to the scribe and to the witnesses to write and sign and deliver a bill of divorce to his wife, and they wrote and signed and delivered it, and it is found to be invalid or it was written and lost, they may write a new bill of divorce. If it was not lost, and they are unsure whether it is valid based on some stringencies regarding which they were accustomed to being stringent, they have fulfilled their mission and must return to the husband, who can then tell them to write and sign [a new bill of divorce]. Rem"a: If the witnesses want to write a new [bill of divorce] and both would deliver it to her, they have permission and need not ask the husband (Responsa of Rashb"a cited in the Beit Yosef). Therefore if the husband leaves the city, he should say that he gives them permission to write and sign anywhere from one to one hundred bills of divorce until one is valid both in its content and its signatures according to the Rabbi of the city beyond any doubt. Rem"a: And according to anyone who displays it (Seder Gitin). But if the husband is in town, one must not rely on this and the husband may go back and command the witnesses and the scribe each time [the bill of divorce needs to be rewritten] (Beit Yosef citing Rabbeinu Tam). Such is our custom, that [the husband] goes back and commands as he did originally, and also gives them the parchment and the ink if the scribe does not have any left over from that which he gave him originally (this is found in Seder Gitin). Some say that that which we say, "The witnesses and scribe fulfilled their mission, [so the husband] must go back and command them again," only applies is it was already signed and invalidated. If, however, it still has not been signed, they may write a new one and the husband need not command it (Beit Yosef citing the Rashba"tz), but the custom is to be stringent on all issues.

If he wrote for them, "Write [the bill of divorce], sign it, and give it to a messenger and he will take it to her," and they wrote it and gave it to a messenger and the bill of divorce was found to be invalid or nullified, they do not write a new bill of divorce until they confirm with the husband. If they did not confirm with him and they wrote a new, valid bill of divorce and gave it to the messenger and he gave it to her, it is doubtful whether she is divorced. Rem"a: There are those who say that whenever the bill of divorce is found to be nullified or invalid they write a new bill of divorce, but if the messenger lost it, the law is as has been explained (Tur). All this applies when he told them to write it and deliver it, but if he gave a bill of divorce to a messenger to bring it and it was found to be invalid, it is clear that they cannot write a new one without his permission (Beit Yosef citing Responsa of the Rashb"a, and also implied in Responsa of the Ramba"n #145).