I need help with this Business law questions with full explanation that I am trying to understand it

Do you think Duty of notify, Duty to ACCOUNT, duty of loyalty is violated this case?

Thanks?

Mary contracts with John for John to be Mary's agent on December 1, 2019.The contract requires that John travel across Maryland in search of antiques for Mary's store.Mary particularly wants John to locate and purchase antique teddy bears.The contract states that John is allowed to spend up to $5,000 on any item he finds that fits Mary's needs and tell her what he bought.He must contact Mary if he needs to spend more than $5,000 on an item.Mary provides John with a list of 100 names of antique collectors who may be interested in selling.

John decides that he will not contact the people on Mary's list.Instead, he drives around Maryland stopping at antique stores and garage sales looking for items.On January 2, 2020, John finds a very rare teddy bear.The price is $7,000.He decides not to tell Mary about the teddy bear.Instead, he buys it for himself.He immediately drives home after buying the bear and lists it on eBay

Can you explain to me which duty is violated if any ?

Thank you