Abu Hurairah (RAA) narrated that The Messenger of Allah (ﷺ) said:

"None of you should fast a day or two before the (beginning of the) mouth of Ramadan, unless it is a day on which one is in the habit of fasting (i.e. voluntary fasting that coincides with that day).” Agreed upon.

عَنْ أَبِي هُرَيْرَةَ ‏- رضى الله عنه ‏- قَالَ: قَالَ رَسُولُ اَللَّهِ ‏- صلى الله عليه وسلم ‏-{ لَا تَقَدَّمُوا رَمَضَانَ بِصَوْمِ يَوْمٍ وَلَا يَوْمَيْنِ, إِلَّا رَجُلٌ كَانَ يَصُومُ صَوْمًا, فَلْيَصُمْهُ } مُتَّفَقٌ عَلَيْهِ [1]‏ .‏