What event led the British to end the Townshend Acts?

The British were looking for ways to increase revenue in their colonies. The colonies were becoming more expensive to operate, and the British believed the colonists should share in some of the cost of running the colonies.
The Townshend Acts placed taxes on imported products such as glass and tea. It also removed the power of the colonial legislatures to determine the salaries of the colonial governor. This allowed the colonial governor to act without fear of retaliation by the colonial legislature.
The colonists were unhappy with the provisions of the Townshend Acts. On March 5, 1770, there was a clash between the colonists and the British soldiers in Boston. Five colonists were killed in this event, which was called the Boston Massacre.
Because tensions were high as a result of the Boston Massacre, the British removed all of the taxes from Townshend Acts except for the tax on tea.
https://www.history.com/topics/american-revolution/townshend-acts

https://www.ushistory.org/us/9d.asp