Blank service tag & asset tag on purchased motherboard

Hello,

My motherboard died on my daughter's laptop and I purchased a replacement motherboard on ebay but instead of buying the same model number 3593 i5, I bought a compatible upgrade of an i7 3793. I took to the shop and they made the switch, but said the laptop is asking for the service tag and asset tag of the replacement motherboard ( i7). Looks like the I.T dept of the company it belonged to wiped it clean bc it reads none installed when I went to manufacturer mode. How do I get my laptop operating. Please help