範囲 and 領域: an included range, territory, and field
Compare a range that a voice reaches with animal territory and a field of expertise, using the modifier and the stated activity.
What falls within 範囲
範囲（はんい） means a range or scope. 「声が届く範囲に全員が集まった。」 says that everyone gathered within the range the voice could reach. 声が届く defines that range.
「試験の範囲は教科書の五十ページまでです。」 gives the test's scope as the textbook through page fifty. 範囲 can concern included content as well as space; the sentence does not report that studying is complete.
Whose territory or which field
領域（りょういき） means a territory or field. 「この先は野生動物の領域なので、人は立ち入らないほうがいい。」 says that the area ahead is wild animal territory and recommends that people not enter. The recommendation does not report an entry.
「自分の専門領域を越える問題については、専門家に相談した。」 describes consulting a specialist about a problem outside one's field of expertise. The limit crossed concerns expertise, not departure from a physical place.
Overlap in spatial uses
The 範囲 examples identify how far something reaches or what is included. The 領域 examples identify an animal's territory or a specialist field. Their spatial uses can overlap.
範囲 is not confined to quantities, nor 領域 to physical space. The modifiers and actions distinguish hearing range, animal territory, and a field of expertise.
What does going beyond a 専門領域 mean in 「自分の専門領域を越える問題については、専門家に相談した。」?
Show the answer and why
The problem is outside one's field of expertise. Consulting a specialist is stated, but leaving a physical place is not.