Walmart Inc (WMT  ) faced a significant technical issue in March, leading to widespread mispricing across its self-checkout systems.

The glitch, which occurred on March 19, resulted in customers being charged incorrect prices for various items.

Some prices were lower than listed, while others were higher. This incident affected 1,600 stores nationwide.

According to documents reviewed by Bloomberg, the problem arose from a failure in the system that updates product information for self-checkout kiosks.

Walmart acknowledged the error and stated that efforts to fix the issue had been ongoing for two days. Over 80% of affected customers being reimbursed.

However, the company did not disclose how many customers were overcharged or the total amount involved.

The technical glitch caused confusion and frustration among shoppers who noticed discrepancies in the prices at self-checkout stands.

Walmart's spokesperson, Mischa Dunton, told Bloomberg that the issue led to overcharges averaging 1.88% of the total basket size for affected customers.

Despite the company's efforts to reimburse customers, legal experts suggest that the incident could violate consumer protection laws at both state and federal levels.

The pricing mishap is one of many technological challenges Walmart has faced recently. In February, cash register outages disrupted operations, and issues with photo and vision prescription orders were reported in March.

Legal experts stress the importance of a thorough investigation into the cause of the mispricing and assurances that such issues will not recur.

Walmart stock has gained more than 33% in the last 12 months. Investors can gain access to the stock via the Consumer Staples Select Sector SPDR Fund (XLP  ) and Vanguard Consumer Staples ETF (VDC  ).

Price Action: At the last check on Thursday, WMT shares were trading lower by 0.03% at $64.90.