This was rejected because of repetition.

May I add to @Jill_C's and @yamato713108855's remarks: your asset exposes a lot of noise. 

As @daniellei4510 points out: Rejections for similar images submitted are quite erratic. I suspect that the tool the moderators are using is poorly calibrated, and most moderators take the tool's verdict without checking. That's just my suspicion, though.

Before submitting to AdobeStock, check your image at 100% magnification on your computer monitor.

The bridge is out of focus or slightly blurred.

The image would also have been rejected for quality issues, such as the artifacts in the sky.

It has pretty much been established by example that the "too similar" rejections are often arbitrary and sometimes in error. But one way to tell is to go to Adobe's stock site and drop your image into the page to look for similar examples, as though you were a buyer. Sometimes, but rarely, the results are legitimate. Presently, I have 190 rejections for "similar" images, lowering my 98% acceptance rate by about 2 or 3 percentage points. For a few of those rejections, I've revised keywords and titles and had them eventually accepted, so I do believe keywords and titles have something to do with this particular rejection. Meanwhile, contributors have slowed down or stopped contributing altogether due to this issue. Myself, if I get rejections for images being too similar, I submit those to other stock sites.