Welcome to the Community, @Chiromom.

At this time, QuickBooks will automatically assign check numbers even the transactions are ACH or draft.

I can see how seamless your work will be if you can enter transactions for ACH alone. However, the best that we can consider right now is to delete those ACH transactions as what you've performed.

But I want to let you know that your voice matters and I'm submitting feedback directly to our product engineers for consideration. For now, you can visit our blog site so you'll be able to get the latest news about QuickBooks and what our Product Care Team is working on. 

Please keep in touch if there's anything else I can do to help you succeed with QuickBooks. I've got your back. Have a great day!