I never saw the Messenger of Allah ﷺ fast two consecutive months except that he would join Shaban with Ramadan.
أخبرنا شعيب بن يوسف ومحمد بن بشار واللفظ له قالا حدثنا عبد الرحمن قال حدثنا سفيان عن منصور عن سالم عن أبي سلمة
ما رأيت رسول الله ﷺ يصوم شهرين متتابعين إلا أنه كان يصل شعبان برمضان
[Sahih] Narrated by Tirmidhi, The Book of Fasting, chapter on what has been said about joining Shaban with Ramadan, no. 736, from Muhammad bin Bashshar, from Abdul-Rahman bin Mahdi, from Sufyan Thawri, with this wording. He said, hasan. It is also found in al-Kubra, no. 2485, and it has sahih corroborating narrations. See the following hadith.