If a franchise owner returns a client back(janitorial-commercial cleaning business) how can they be charged fees for losing when it's given back

my husband had an account that the cleaning business gave him which he paid fees on for them finding ti. He paid all fees and kept account for several years. He did not want the account any longer and gave it back to the franchise to find someone else to do. That meant new person would have to pay fees . My husband was charged a fee stating that he lost the account. Not true, he gave it back. Is that legal?