The Messenger of Allah ﷺ said, "There are no people who gather to remember Allah, seeking nothing by it except His face, but a caller from heaven calls out to them, 'Rise, you have been forgiven. Your evil deeds have been exchanged for good ones.'"
حدثنا محمد بن بكر أخبرنا ميمون المرائي حدثنا ميمون بن سياه
عن رسول الله ﷺ قال ما من قوم اجتمعوا يذكرون الله لا يريدون بذلك إلا وجهه إلا ناداهم مناد من السماء أن قوموا مغفورا لكم قد بدلت سيئاتكم حسنات
Its chain is hasan because of Maymuni, and it has already preceded in similar wording at 9245, and it is also found in the Sahihayn.