please can you assist me to resubscribe because today is my last day to do that in other to maintain my old subscription?

You can resubscribe to your previous plan or subscription in the Subscriptions and billing tab.

Go to the Gear icon > Subscriptions and billing > Resubscribe. Enter the updated company information, then follow the on-screen instructions.

For details on checking your next charge date, visit this article: Resubscribe to QuickBooks Online.

Leave a comment below if you have any other questions or need clarification.