Did you fill out 2 schedule C forms? You only needed to do 1 schedule C for all her music teaching. I would delete one and add it to the other sch C.
When you are self employed you are in business for yourself. Use your own info and address etc. The people or company that pays you is your customer or client.
And actually you can just enter it as Other self employment income or as Cash or General income. You don't need to get a 1099MISC, 1099NEC or 1099K. Even if you did you can enter all your income as Cash. Only the total goes to schedule C. You should be entering the income from your own records.
