Please let me help you with 〜させてください

Grammar Explanation: Please let me with 〜させてください

ARIA The MASTERPIECE » Volume 3 » Page 287

Akari meets Woody as he’s out on a delivery run, but he’s in a spot of trouble because he forgot to bring his map, and there isn’t enough time for him to go back and get it. Akari is familiar with the city, and realizes she can lend him her knowledge.

灯里(あかり):: 「あっ…　あの！」; “Ah, um!”; 「もしも私(わたし)でよかったら…　お手伝(てつだ)いさせてくさだいっ！」; “If I would be okay... Please let me help you!”

The verb する becomes the causative させる.