Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
$99.99 might be a subscription for Microsoft365 Family.
Possibilities on why it may be there include a auto-renewal, or accidental purchase, or someone in your family purchased using your credit card.
It can also be because your credit card details were stolen from elsewhere and someone got a hold of it, sold it to others, and at some point it is now used for this subscription.
If you are absolutely sure this has nothing to do with your end and suspect fraudulent use, the quickest method might be to dispute the transaction with the bank.
Personally, each year I have weird transactions from US merchants on my credit card, usually for credits, gift cards etc which I know nothing about. I simply dispute this with my bank and get new cards issued. The banks would insist issuing new cards as they claim once the information has been leaked, they are not liable for future fraudulent charges.