He is asking about ruqyah for protection against black magic
Question

I saw a man in masjid after asar prayer who was moving his finger in circles,and doing some other stuff, this was something I have never seen before, so I asked him and he said this is "hisar" a type of ruqya to protect from black magic, when I asked for the evidence he said this is proven from hadis however he himself have never seen the hadis and his elders(sufis) have been doing this since many years. What is this thing "Hisar"?
Praise be to Allah.We have not come across any hadith which speaks of what you mention of “hisaar” or protection against black magic.
It is not permissible for anyone to attribute any hadith to the Prophet (blessings and peace of Allah be upon him) unless he is certain of its soundness, because the Prophet (blessings and peace of Allah be upon him) said: “Whoever tells a lie about me deliberately, let him take his place in Hell.” Narrated by al-Bukhaari (107) and Muslim (3). And he said: “Do not tell lies about me, for whoever tells lies about me will enter the Fire.” Narrated by al-Bukhaari (106).
 And he said: “Whoever attributes a hadith to me, knowing it to be false, is one of the liars.” Narrated by al-Bukhaari (1).
Allah, may He be glorified, has prescribed for His slaves that by means of which they can protect themselves against magic and other evils before they happen, by His leave. That includes the following:
a.
Constantly obeying Allah, by doing everything that Allah has enjoined upon His slaves and avoiding everything that is prohibited; sincerely repenting from all sins and bad deeds; seeking to draw closer to Him, may He be glorified, by doing supererogatory (naafil) acts of worship; putting one’s trust in Allah, seeking His help, and turning to Him alone. Hence it is narrated from the Prophet (blessings and peace of Allah be upon him) that he said: “Be mindful of Allah, and He will take care of you; be mindful of Allah and you will find Him before you. If you ask, then ask of Allah, and if you seek help, then seek the help of Allah.” The hadith was narrated by Imam at-Tirmidhi, who said: It is a hasan saheeh hadith.
b.
Persisting in reciting the adhkaar of morning and evening, which includes the following:

Reciting Aayat al-Kursi and the last two verses of Soorat al-Baqarah following every prayer and when going to sleep.
Reciting Soorat al-Ikhlaas and al-Mi‘wadhatayn three times. It was narrated from the Prophet (blessings and peace of Allah be upon him) that he said: “Reciting Qul Huwa Allahu Ahad and al-Mi‘wadhatayn in the evening and in the morning will suffice you against everything.” Narrated by an-Nasaa’i and classed as saheeh by al-Albaani.
Saying “Bismillaah alladhi laa yadurru ma’a ismihi shay’un fi’l-ardi wa laa fi’l-samaa’i wa huwa al-samee’ al-‘aleem (In the name of Allaah with Whose name nothing on earth or in heaven can cause harm, and He is the All-Hearing, All-Knowing).” It is proven from the Prophet (blessings and peace of Allah be upon him) that whoever says this three times, nothing will harm him.
Saying “A‘oodhu bi kalimaat Allaah il-taammati min sharri ma khalaq  (I seek refuge in the perfect words of Allaah from the evil of that which He has created)” three times, and other words that have been narrated.
Eating seven dates in the morning, before eating or drinking anything else. It is narrated from the Prophet (blessings and peace of Allah be upon him) that he said: “Whoever eats seven ‘ajwah dates in the morning every day, no poison or magic will harm him during that day.” Narrated by al-Bukhaari.

End quote from the website
What the Muslim must do is adhere to the Quran and saheeh Sunnah, and beware of the innovations and myths of the Sufis.
And Allah knows best.