Also to add to this... with both SSD and HDD originally connected in the clone attempt, Windows installation may have detected the other Windows installation on the other drive and installed to the SSD as a dual OS installation which gives you a choice at boot for one or the other. Then removing the HDD and having the SSD remaining the boot manager isnt smart enough to test for this HDD and so it boots off of the SSD and gives option for the HDD which is no longer connected. If this is the case then its a simple fix as shared in Patio's link.
However if you had the cloned copy of Windows onto the SSD and then decided that that wasnt working out so well and decided to then perform a clean installation, Windows on installation searches drives for Windows installations. It is possible to breeze past an important option to not have the other Windows installation remain, and so you can have 2 installations of Windows on the same drive, one that is functional and the other that is not, or you can have 2 installations of the same OS both functional. The problem here is that each installation takes up drive space and so if this is what happened then you will have to determine which Windows install is the one that you do not want and manually delete it to get say 20GB back which is otherwise wasted with the initial install that you really want gone from the drive, but otherwise remained through the process of the 2nd installation.