That is a type of Oenothera or evening primrose! This article will help: https://www.gardeningknowhow.com/ornamental/flowers/evening-primrose/yellow-evening-primrose-plant-wildflower-in-the-garden.htm
We had a very hot summer - most days over 30 deg. C.
Unfortunately, it is hard to say without knowing exactly how they were cared for, and the environment that they grew in. Unfortunately, to flower at their best, they need a somewhat specific set of conditions, though they are hardy and will grow pretty well otherwise.
Likely conditions that would stop flowering would be too much sun, not enough moisture, too much nitrogen in the soil while not having enough phosphorus and potassium in the soil, among other things. Fortunately, these things can be tested.
Here are some articles that will help:
What kind of flowers are these
Its a Primula species.
I would like to divide these three different flowers. Please notify me as to what these flowers are and how do I divide them and transplant them? Thank you very much.
The first is the Evening Primrose (Oenothera fruticosa). The second is the common Daylily (Hemerocallis fulva). The third will be Loosestrife (Lysimachia punctata or similar).
All are considered invasive or naturalized in most areas. With this being said, transplanting them will be as easy as taking a clump and putting it in the desired location. I would start with putting them in container and transplanting after recovery, in my experience, though!
you try to pull off the stem you pull up the plant Below is a photo of mine in bloom. I don’t have a photo of them stem form
I would mow or prune them with shears. This will avoid pulling up the root.