The Prophet ﷺ said: When one of you prays, and he does not know whether he prayed more or less rak'ahs (than those prescribed by the Shari'ah), he should perform two prostrations while he is sitting. If the devil comes to him, and tells him (suggests him): "You have been defiled," he should say: "You have told a lie," except that he feels smell with his nose, or sound with his ears (then his ablution will break). These are the wording; of the tradition reported by Aban. Abu Dawud said: Ma'mar and 'Abi b. al-Mubarak mentioned the name "Iyad b. Hilal and al-Awza'i mentioned the name of Iyad b. Abi Zuhair.
أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ إِذَا صَلَّى أَحَدُكُمْ فَلَمْ يَدْرِ زَادَ أَمْ نَقَصَ فَلْيَسْجُدْ سَجْدَتَيْنِ وَهُوَ قَاعِدٌ فَإِذَا أَتَاهُ الشَّيْطَانُ فَقَالَ إِنَّكَ قَدْ أَحْدَثْتَ فَلْيَقُلْ كَذَبْتَ إِلاَّ مَا وَجَدَ رِيحًا بِأَنْفِهِ أَوْ صَوْتًا بِأُذُنِهِ وَهَذَا لَفْظُ حَدِيثِ أَبَانَ