We'll have to turn on the custom transaction numbers option so we can customize our check number, janebinaustin.

This way, we'll have the option to create a check starting with number 3100. I've got the steps on how to do it:

1. Click the Gear icon, and then select Account and Settings.
2. Go to the Sales tab.
3. Click the pencil (edit) icon on the Sales form content section.
4. Tick Custom transaction numbers.
5. Click Save, and then Done.

Once done, let's try creating a check. Then, make sure that it starts at 3100. Afterward, the system will automatically follow the the order.

For us to change the check number that we've previously entered, we'll have to manually open and enter the correct number one by one.

You can check this article in case you want to print checks: How to print checks.

You always have me if you have concerns when printing a check.