I did a brief stint in the call center (before I found a job that didn't make me miserable). When it comes to calling about the bill or charges, the biggest factor is how you interact with the representative. People that call about the bill tend to be very nasty people thinking that added pressure will get them what they want, the nice ones are in the minority. Fun fact - the nicer ones tend to get what they want more often.

For those that were aggressive/verbally abusive - I would stick to the policy to the very letter. If there was a statement/rule that would prevent them from getting a dime, damn straight I made sure they got nothing. Other times their issue was legitimate, but going by the policy would only offer them a measly $1 - $2. "It shows that you didn't have wifi coverage, but it also shows here that you still had internet service during this time. This is the most the system will let me give you." My supervisor actually had our backs as well. If someone was nasty and the call was escalated, they would walk away with nothing.

OTOH if you were nice to me I would bend over backwards to help you. "It shows here you didn't have wifi coverage for a bit, I'm going to extend that to include you didn't have any internet service in order to give you a much better credit". Things like that I was able to justify with my supervisor, and it was a win-win for everyone.

Moral of the story, it's not so much about creating conflict as it is about being polite. Treat the representative well and they will return the favor. Act like a dick and walk away with little to nothing. Accounts have notes as well, so those that tried to abuse the system or were frequently cruel wouldn't get jack shit.