Sounds like it is adjusted too tight and the blades are binding against the bed. Try setting it back a bit. If it will only cut cleanly with that tight a fit I suspect warping somewhere in the cutting train. Or if it is tight no matter the setting then it is binding elsewhere. If you can't adjust it then don't fiddle with it. Just get a refund.

A neighbor (Not a close one) gave me a really nice looking reel mower--said it didn't work very good.
So, last week, i got to it. Took it apart so i could grease everything, and then put it all back together.
I did that part of the job correctly.
Let me say-that mower was probably a money pit, because the previous owner said they had it back to the dealer several times, but it never worked right.
Well, somebody else has it now--i parked it out by the phone pole, and next morning, it had found a new home!

Reel mowers are great for people who like to spend lots of time maintianing and otherwise fiddling with them. Or paying someone else to do the work. For most of us a rotary will do just fine.