Increasingly, American customer support people are being laid off, with their jobs being replaced by computers and/or by overseas operators.
If you have trouble understanding an overseas operator, first ask the agent their name and agent id and write it down. Then tell them you are having difficulty understanding them (be polite!) and ask to be connected to a "second level" (or "tier 2" manager). The managers are usually in the USA or at least they are usually better trained with American accents.
If you can not get service from someone who understands you, be sure to let us know. If a company repeatedly has hard to understand support representatives, that company will get a bad rating and will be published on our list of worst companies in the US.
Of course, also check if we have hints for the specific company you're trying to call in our customer service database.