The Prophet ﷺ forbade the mixing of ripe and unripe dates and also the mixing of dates and raisins (for preparing a syrup) but the syrup of each kind of fruit should be prepared separately. ( One may have such drinks as long as it is fresh )  

نَهَى النَّبِيُّ ﷺ أَنْ يُجْمَعَ بَيْنَ التَّمْرِ وَالزَّهْوِ وَالتَّمْرِ وَالزَّبِيبِ وَلْيُنْبَذْ كُلُّ وَاحِدٍ مِنْهُمَا عَلَى حِدَةٍ  

Prepare Nabidh from each one of them separately.  

نَهَى رَسُولُ اللَّهِ ﷺ عَنِ الزَّبِيبِ وَالتَّمْرِ وَالْبُسْرِ وَالتَّمْرِ وَقَالَ يُنْبَذُ كُلُّ وَاحِدٍ مِنْهُمَا عَلَى حِدَتِهِ  

Prepare Nabidh from each one of them separately. (Using translation from Muslim 1989a)  

نَهَى رَسُولُ اللهِ ﷺ عَنِ الزَّبِيبِ وَالتَّمْرِ وَالْبُسْرِ وَالتَّمْرِ وَقَالَ يُنْبَذُ كُلُّ وَاحِدٍ مِنْهُمَا عَلَى حِدَةٍ  

[Machine] I heard the Messenger of Allah ﷺ forbidding the mixture of dates, dried yogurt, and fresh dates. He said, "Drink each one separately."  

سَمِعْتُ رَسُولَ اللهِ ﷺ يَنْهَى عَنِ الْخَلِيطَيْنِ التَّمْرِ وَالْبُسْرِ وَالرُّطَبِ وَقَالَ اشْرَبُوا كُلَّ وَاحِدٍ مِنْهُمَا عَلَى حِدَتِهِ  

"The Messenger of Allah [SAW] forbade mixing Al-Busr and raisins, and Al-Busr and dried dates, and he said: 'Soak each one of them on its own.'" (Using translation from Nasāʾī 5570)  

سَمِعْتُ أَبَا هُرَيْرَةَ يَقُولُ نَهَى رَسُولُ اللهِ ﷺ أَنْ يُخْلَطَ التَّمْرُ وَالزَّبِيبُ وَالْبُسْرُ وَالتَّمْرُ وَقَالَ انْبِذُوا كُلَّ وَاحِدٍ مِنْهُمَا عَلَى حِدَتِهِ