What should I do about my job?

Hello! I’m in a work dilemma. I currently work for the post office (mornings) and it’s part time and it’s a really easy office to work at but I have to work 6 days a week and honestly have no idea if or when I will become full time. I have an opportunity at another company which is full time at about the same pay and it’s remote. The only downside that it’s customer service and I’m afraid I will get burned out and hate it. Anyone in the customer service world that can ease my mind?