in the chart of accounts, create a current asset account called pre-paid utility

make your payment and use that account as the expense for the payment

when you want to apply that pre-payment to a bill
enter the bill, and the utility expense account and amount
on the next line select the pre-paid account […]

Resolution for 'allocate prepayments issue: 'how do I record and allocate prepayments to a utility' available: Yes.

The allocate prepayments issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the allocate prepayments issue yourself by looking for a resolution described in the article. If it is a complex allocate prepayments issue or you are unable to solve the issue, you may contact us by clicking here or by using other allocate prepayments support options.

For more information about resolving issues related to allocate prepayments in Quickbooks/QBO or to get support for the issue 'how do I record and allocate prepayments to a utility', click the link below: