What is the daily or monthly limit of subscription and how to upgraded into unlimited result

My Plan details:-
FlightXML3 Plan: Bronze
Auto-Upgrade: On
Monthly Query Limit: 2,500
Queries Used: 2,649
Queries Left: -149
Billing Date: 30th of the month

When we trying to hit API we receive this message:-
Your account has exceeded the allowed limit of your subscription.
Please tell me how we upgraded into unlimited result.