Meanwhile I see people picking it up within days.What am I doing wrong?

Why, because you need people to buy those houses, and people's incomes only rise at the rate of inflation. 

People have been telling me for a while to get on this app because of the types of properties and sellers I work with.

If they want it rectified now, they can pay for the rekey process OR they can have their mail held and keep looking for the lost key.

I have noticed a trend over the pasts 10 years where more and more of the people have zero involvement in the day-to-day operations of the property and are only raising money.  

Without it, you're really relying on other people's perceptions.

If you do, you risk getting bad reviews even if you warn people. 

Judicious use of leverage (debt) when the property will still cash flow positive after debt service; when there’s enough equity left in the property to refinance if advantageous, and when sufficient reserves are held to cover vacancies, recessions, and unexpected repairs5.

You can have (2) people on the same loan or more. 

I have 50+ people on my contracting company only working on the houses I buy and am speaking from that experience starting with zero contractors less than 3 yrs ago and having been burnt very had multiple times throughout the process.