[Hope]

Your interpretation might be wrong..angels are also Allah messengers.

Scholars say there are two reasons why angels are called "messengers". The first one is that they are Allah's messengers sent to people. They deliver revelation to prophets, give inspiration to righteous people and show true dreams to people in general.

See you learn something new everyday..

Praise be to Allah, Who created (out of nothing) the heavens and the earth, Who made the angels, messengers with wings,- two, or three, or four (pairs): He adds to Creation as He pleases: for Allah has power over all things." (Fatir, 35/1)

As per Islam, Angels delivered messages only to prophets and messengers.

Which scholar said that angels deliver messages to righteous people and show true dreams to people?

Please don’t mix your belief here.