Help needed Toro Super Recycler

I began a lawn care biz this year. Starting from scratch I was not looking to spend 2000 on a mower.

I bought a Toro Super Recycler. I realize it is not a "commercial mower". Maybe I am dumb but I felt I could get by with that until I was doing 20 yards or so per week and then step up.
Ill give details of my experience so far and maybe someone with far more knowledge can point me in the right direction.

(All square feet measurements are fairly close but not exact)

I began my mowing season on April 7th.

In 3 weeks I mowed 18,500 sq ft. The mower began losing power so I put in a new air filter, spark plug, and hit the carb with carb cleaner. I then mowed 15,100 sq ft before it quit running completely.
So 1 month and 33,650 sq ft

It goes to the shop and they replaced the carb which I paid for.

I picked it up and it quit again after only 2 weeks and 34,000 sq ft.

It went back to the shop where they said the needle valve was swollen so they fixed it for free and suggested buying gas soewhere else. I was running gas that was "up to 10% ethanol".
But now I searched and found zero ethanol and that is all that i have used since.

This time it ran for 4 weeks and did mow 64,000 sq ft. Its hardest working day yet was 19,000 sq ft.
Now it has quit again. It feels like it is losing power and then it did stop. Now when I try starting it runs and dies within 30 seconds.

The shop says it is just because it is meant to only be a homeowner mower. I understand it not handling 50 yards a week. But I feel it shouldn't be giving this much of an issue for how I use it. I am mowing one day a week and its largest amount was 19,000 sq ft. I don't think I am asking too much from it at this time.

I got a 10 year old Lawn Boy for free from facebook and it is running 10% ethanol and running with no issues at all whenever this brand new one is in the shop! The lawn boy is smaller and the self propel isn't working so its not as easy btw.

Any advice from someone more knowledgable is greatly appreciated!