Ibn Umar had a friend from the people of Sham with whom he used to correspond. Abdullah bin Umar wrote to him, "It has reached me that you have spoken about something concerning divine decree. Do not write to me again, for I heard the Messenger of Allah ﷺ say, 'There will arise in my nation people who deny divine decree.'"
حدثنا أحمد بن حنبل قال حدثنا عبد الله بن يزيد قال حدثنا سعيد يعني ابن أبي أيوب قال أخبرني أبو صخر
كان لابن عمر صديق من أهل الشام يكاتبه فكتب إليه عبد الله بن عمر إنه بلغني أنك تكلمت في شيء من القدر فإياك أن تكتب إلي فإني سمعت رسول الله ﷺ يقول إنه سيكون في أمتي أقوام يكذبون بالقدر
Its chain of transmission is hasan.Tirmidhi narrated it in the chapter on qadar, the section on the warning against those who deny qadar, hadith no. 2152, and Ibn Majah, hadith no. 4061, from the hadith of Abu Sakhr Humayd bin Ziyad, through this route. Tirmidhi said, hasan sahih gharib. It is also found in Musnad Ahmad, 2/90.