All photos not accepted

Only one example: IMG_1821.JPG

Overexposed sky, underexpose building bad framing (the flag should not melt into the building). Just using the auto adjust button creates a better image!

For such images, you need to take different exposures, as either the sky is overexposed or the building under exposed.

With a quick flip through the photos, I can confirm they all have technical issues.  The only one I was on the fence about was the frog.  I think a stronger composition where the frog didn't blend in with the background and this one may have passed.

Did all of these have technical issues listed for the rejection reason?

IMG_1912.JPG - too little is in focus, and the edges if the yellow flower are overexposed 

IMG_1894.JPG - overexposed, and the branch is not completely in focus. There's also a bit of chromatic aberration

IMG_1905.JPG - not in focus

IMG_1899.JPG - too little is in focus

Adobe Stock is  overrun with floral images, with more than 29 million in the database. While capturing and editing such images for your own use can be fun and good practice, don't bother submitting them to Adobe Stock. Your chance of ever selling one is close to zero.