Can't merge, can't move

I'm trying to merge …/text/watchman_onward_to_your_stations into …/text/watchmen_onward_to_your_stations but when I try to merge them it says it can't be done because the “watchmen” one doesn't exist, and when I try to move it instead it says the new ("watchmen") page I'm trying to create already exists and would I like to merge them instead. Then again, can't merge because the target page address doesn't exist… The “watchman” one has five or six instances, and the “watchmen” one has 27 instances. They are the same hymn. They should be combined. Only one of the “watchman” instances actually has a[n] “…man” in the page scan; I have successfully corrected the instances I had scans for; the one a one actually says “watehman”!