I don't know what the first one in the list means. I'm not accumulating debt currently. The 2nd one makes no sense as I've never been late. The third one can't be right. I carry no balance forward month to month. The 4th one only makes sense if you look at the fact that they keep hacking my limit, but again the balance is always 0. WTF gives??? I have a 740 credit rating, and a mountain of student loans, but other than that I have 0 credit card debt.
		
		
	 
Do you use your credit cards?  If so, your balance isn't $0.  If your balance was $0, then you aren't using your credit cards.  There are two completely different balances to remember.  One balance is the current amount of money you owe them (that is, if they sent a bill today, how big would the bill be?).  If you use your credit card, this is NOT $0.  This is the balance they are talking about in their reasons to lower your credit limit.  The second balance is how much of the last bill did you pay.  You say you pay your bills in full, thus this second balance is $0.  But, that second balance is used ONLY to calculate interest they charge ($0 in your case).  The first non-zero balance is used for absolutely everything else. 
 
If this was your main credit card, then it is a self-fulfilling problem.  Suppose your typical balance is $500.  Remember this is how much you owe at the moment, not what the last bill was and it has nothing to do with how much you paid on the last bill.  Then, your balance to credit limit was $1000 / $8000 = 6.25%.  6.25% is perfectly fine and normal, but banks started getting scared 2 years ago and started cutting limits.  Suddenly your ratio increased to 8.3% when they cut your limit.  Then it sent to 50% when they cut again.  Now you were in big trouble, a 50% utilization is the death signal for credit card companies.  They will just keep cutting until you stop using the card.
 
I'd check your credit report if I were you.  There may be an error, a stolen identity, etc.  That will help explain some of the unknown problems (such as a deliquency or balances that are falsely being attributed to you).
 
Finally, you identified one major potential problem in your OP "a mountain of student loans".  Student loans are in your credit report.  They still count against you, despite being a better kind of debt.  Also, they are easy to go deliquent if you aren't on an automatic payment program.  One misfiled piece of paper and suddenly credit card companies think you should be paying the bill and you aren't.  You might want to rethink that mountain of debt.