The Night Journey - 17:59
The fact that those before denied them did not prevent Us from sending signs. For example, We had clearly given the camel to Thamud. But they wronged him. We send the signs only as a warning.
Allah can send down a sign (miracle) whenever He wills:
The Poets/26:4
And if We willed, We could send down upon them a sign from the sky, and they would submit to it.
The Night Journey/17:59
The fact that those before denied them did not prevent Us from sending signs. For example, We had clearly given the camel to Thamud. But they wronged him. We send the signs only as a warning.
Prophet Jonah/10:99
Had your Lord willed, all those on the earth would have believed. Then will you force the people to believe?
The Cattle/6:37
"They say: "Should not a sign (miracle) have descended on him from your Lord!"Say: "Allah can send down a sign whenever He wills, but most of them do not know it."