I'm a beginner so I'm pretty clueless. I recently bought a Marine band in C. I have been playing around with it for a while before I really started practicing and it sounded fine. I was able to get good solid tones on all the holes both drawing and blowing, however I recently started practicing 2nd position blues scale. After 4 draw and 4 draw bend I can barely get any tone from the 4 blow. Conversely if I can get a solid tone from 4 blow the 4 draw bend becomes impossible.
I assume it's not broken as I can get the tones individually, it's going from one to the next makes it sound awful if I can even get it to make a sound in the first place.
Does any of this make sense? If so is it me or the reed?

I'm not really sure, but it sounds to me like you might have some debris blocking the reed from performing correctly. If that is the case, try tapping it against a hard surface to try and shake it lose. Sometimes it works, sometimes it doesn't. Hope this helps.

If it doesn't work, take the covers off and look closely. You might rinse the debris away, or you might carefully pick it out with something.