Plan renewal

I’m looking to renew my plan and maybe add mobile services.  I have chatted with a few people online a few weeks ago. They were rude and did not help. Today, I spoke to a sweet lady with heavy accent and unfortunately hard to understand. 
I really would like to speak to an US based agent. 
How can I reach someone in the US that can help me find a promotion and renew my plan? 
Thank you in advance!