The actress, 42, is being sued by American Express for failing to pay her current outstanding balance of $37,981.97 since last summer, according to court documents obtained by PEOPLE.
Per the documents, Spelling's last activity was on June 26, when the Beverly Hills, 90210 star tried to make a payment in the amount of $1,070, but the transaction failed to complete.
Spelling's last payment was due on Aug. 18, with a minimum amount of $1,477 owed (which included the past due amount of $1,070).
According to the lawsuit filed Jan. 13, American Express is asking that the mom of four pay the entire balance, including interest, as soon as possible.
On Tuesday, Spelling's mom Candy Spelling – with whom the star has had a rocky and sometimes estranged relationship – told TMZ she isn't sure why her daughter hadn't paid the bill: "I don't know, extravagance, I guess."
Candy also said she's been helping her daughter out.
"I'm paying all her bills now. I'm not paying extras like that, I'm not paying any back payments," she said. "Just for the house and the kids' school and the food."
On Lifetime's Tori Spelling: Celebrity Lie Detector in October, Spelling said she received just $800,000 of her TV mogul father Aaron Spelling's estimated $500 million estate when he died in 2006.
Back in 2013, Spelling opened up to PEOPLE about how she and husband Dean McDermott got through some financial setbacks, which began in 2011 when they sold their Encino, California, home at a loss and Spelling's retail space InvenTORI failed to perform as hoped.
"We're all about repurposing," Spelling said. "It's a really good value to have."
At the time, Spelling told PEOPLE their kids' birthday parties were less over-the-top than they once were, and that they were watching their medical expenses: McDermott, now 49, decided against getting the vasectomy he wanted after their business manager said the couple couldn't afford it.
"We're in the entertainment business, and things change year to year," Spelling said. "We don't have a series on the air right now, so we have to be more restrictive of what we can spend, just like anyone who doesn't currently have a steady job."