Al-Firasi asked the Messenger of Allah (ﷺ): May I beg, Messenger of Allah? The Prophet (ﷺ) said: No, but if there is no escape from it, beg from the upright.
Sunan Abi Dawud Book 9, Hadith 91
← Previous Hadith The Prophet (ﷺ) said: If one who is afflicted with poverty refers it to me, his poverty will not be brought to an end; but if one refers it to Allah, He will soon give him sufficiency, either by a speedy death or by a sufficiency which comes later.

Sunan Abi Dawud Book 9, Hadith 90 Next Hadith → Umar employed me to collect the sadaqah. When I finished doing so and gave it to him, he ordered payment to be given to me. I said: I did only for Allah’s sake, and my reward will come from Allah. He said: Take what you are given, for I acted (as a collector) during the time of the Messenger of Allah (May peace be upon him) and he assigned me a payment. Thereupon, I said the same kind of thing as you have said, to which Messenger of Allah (May peace be upon him) said: When you are given something without asking for it, you should use it for your own purpose and as sadaqah.

Sunan Abi Dawud Book 9, Hadith 92