(((krisakira)))
I am very sorry ~ debt collectors can be awful sometimes!

I definitely understand what it's like to be super-low on funds & bank fees are ridiculously high! I would advise you to call the debt collector and complain.
You have granted them permission to automatically withdraw $50/month from your account. You certainly deserve an explanation, apology, and perhaps a credit to your account for causing unnecessary bank fees. If they are unwilling to do that, than maybe you should contact government officials to come down on the debt collection company.