They are denouncing him for applying the Sunnah and saying that it divides the Muslims

No File Exists
Check below answers in case you are looking for other related questions:
A young woman became Muslim and her family are trying by all means to make her give up Islam; what should she do?
How should he call his friend to the way of al-Sunnah wa’l-Jamaa’ah?

No File Exists
Related Answers:
Who are the Wahhaabis and what is their message?
How to make people aware of the world around them through Friday khutbahs
Saving the Muslims from loyalty to the west in their journalistic writings
A young woman became Muslim and her family are trying by all means to make her give up Islam; what should she do?
How should he call his friend to the way of al-Sunnah wa’l-Jamaa’ah?

Recommended answers for you:
Ruling on women visiting graves
Virtues of the Ten Days of Dhul Hijjah
How should we observe Laylat al-Qadr and when is it?
Ruling on drinking beer
When should a person make the intention to fast, and what if he finds out during the day that Ramadan has begun?