Mercier, Judge. Following a business dispute, Cloudious, LLC (“Cloudious”) sued Think Development Systems, Inc. (“Think Development”) for breach of contract, money had and received, breach of fiduciary duty, punitive damages, and attorney fees. Think Development answered and counterclaimed, asserting claims for breach of contract, money had and received, unjust enrichment, and attorney fees. Cloudious subsequently moved for summary judgment on its claims and Think Development’s counterclaims. The trial court granted summary judgment to Cloudious on its breach of contract and breach of fiduciary duty claims, as well as on Think Development’s counterclaim for attorney fees. As to all other claims, it denied summary judgment. The trial court also denied Cloudious’s motion to strike an affidavit filed by Think Development. In Case No. A23A1042, Think Development appeals the grant of summary judgment to Cloudious. Cloudious cross-appeals in Case No. A23A1043, challenging the trial court’s decision to (1) deny its motion to strike, and (2) deny its motion for summary judgment on Think Development’s substantive counterclaims.[1] For reasons that follow, we reverse the trial court’s ruling in Case No. A23A1042, and we affirm in part and reverse in part the ruling in Case No. A23A1043. Summary judgment is appropriate when “the pleadings, depositions, answers to interrogatories, and admissions on file, together with the affidavits, if any, show that there is no genuine issue as to any material fact and that the moving party is entitled to a judgment as a matter of law.” OCGA § 91156 (c). We review a trial court’s summary judgment ruling de novo, construing the evidence and all reasonable inferences in favor of the nonmoving party. See Wright v. Cofield, 317 Ga. App. 285, 285 (730 SE2d 421) (2012). So viewed, the record shows that Pulukottil Joy is the President and CEO of Think Development, a staffing service that places consultants with other businesses. In March 2006, Think Development entered into a service agreement with Cognizant Technology Solutions (“CTS”) to provide computer programming and technology consultants to CTS. The agreement was updated in 2012 to include, among other things, references to CTS’s “vendor qualification and due diligence processes,” which Think Development was required to meet. In 2016, Cloudious, another staffing and consulting service, approached Think Development about purchasing the CTS contract. Joy met with Cloudious’s sole shareholders, Pascal Vinoth and Subash Yammada, who stated that they had contacts within CTS and could substantially grow the existing staffing relationship. Recognizing that his current business with CTS was minimal, Joy agreed to sell Think Development’s interest in the CTS service contract to Cloudious pursuant to an asset sales agreement (“ASA”) drafted by Yammada. As part of the sale, Cloudious agreed to pay Think Development: (a) One Hundred Thousand Dollars ($100,000.00). (b) 15% of the Gross Margin for proceeds of the contract during First Year. The payment is due half yearly. (c) 10% of the Gross Margin from the proceeds of the contract during Second Year. The payment is due half yearly. (d) 10% of the Gross Margin from the proceeds of the contract during Third Year. The payment is due half yearly. The parties executed the ASA on November 7, 2016, at which point the service agreement between Think Development and CTS was to be transferred to Cloudious. To this end, Vinoth prepared a letter for Joy to send to CTS, stating: This Letter shall confirm and ratify that, [Think Development] and Cloudious LLC have combined together as of today. Effective immediately, our combined firm will begin conducting its practice as Cloudious LLC. The merger is a joining of two extraordinary firms very similar in size and culture, with practice strengths that are highly complementary and will enable us to provide a new and broader set of services to you. We look forward to discussing those in more depth with you. . . . We request you to transfer our existing [service agreement] to Cloudious LLC.[2]