Can unused funds roll over to the following month?

Summary:

We currently have a 12-period monthly budget (January to December), but we're unable to use the remaining balance from previous months.

For example,

Loaded budget January $100. Consumption $0. Available $100 February $100. Consumption $0. Available $100 March $100. Consumption $0. Available $100 April $100. Consumption $0. Available $100 May $100. Consumption $0. Available $100

Total Funds Available in May $500

I'm trying to enter a document for $200 in May, and the system says there are no available funds.

There is an option to transfer the budget from account to account, but it's not feasible because many combinations remain available from previous months.