Earlier this year, Home Depot charged an Oregon customer a $28 late fee for allegedly missing a payment on his store line of credit. The subsequent dispute over that fee resulted in more fees, a 100-point drop in the customer’s credit score and now a $250,000 lawsuit against the retailer.

According to the complaint [PDF] filed earlier this month in Multnomah County, OR, the customer claims that until April 2015, he’d regularly paid his Home Depot bill in full each month.

Then, after making a purchase of $115, the customer says he scheduled an online payment through his bank to pay the full balance on his card on April 26.

This is where things get sticky. The customer claims that the transaction went through on time — or at the very least that it was “delivered within hours or minutes of that date,” which he deems “an immaterial delay.”

Even so, he claims that the retailer hit him with the late fee. But according to the complaint, Home Depot has giving the customer varying accounts of when it actually received the payment — anywhere from 0 to 48 hours after it was due.

The customer called for the late fee be erased from his account, but Home Depot denied his request.

At this point, says the plaintiff, Home Depot “embarked upon a harassment campaign designed to bother, vex and leverage” the customer, resulting in allegedly dozens of automated phone calls.

Even after the customer made requests for the calls to stop, he claims they continued in alleged violation of Oregon state laws against telephonic harassment.

The customer also alleges that Home Depot interfered with his ability to refinance his home loan by falsely reporting the late fee — and the fees that have been added to that late fee — as unpaid debt to the credit reporting agencies.

By insisting to the credit bureaus that the customer was late with payments on a monthly basis, his credit score dropped 100 points, according to the complaint.

Alleges the lawsuit: “Home Depot knew this conduct was wrongful and knew its statements were inaccurate and misleading and made these statements in an attempt to leverage payment to which it was not entitled.”

After he realized that the late fee dispute was going to impact his ability to refinance his mortgage, the customer says he offered to pay Home Depot, but says the retailer refuses to withdraw its previous statements to the credit bureaus.

The lawsuit seeks a court order to correct his credit reports, $209 in damages for the money he paid to end the late fees, and another $250,000 in damages which the complaint says represents the additional interest the customer will have to pay because of the damage done to his credit.

One potential problem with this lawsuit, as noted by the Oregonian, is that Home Depot’s brand may be on the credit card in question, but the actual servicing for the card is done by Citi.

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