Wells Fargo's banking unit double-charged an unknown number of customers due to a technical error, according to a report by NJ.com.

The glitch reportedly affects customers registered to pay their bills automatically online. NJ.com reports that many of those affected were voicing complaints on social media, saying transactions double their bill payments were being deducted by Wells Fargo.

Howie from Maryland tweet

Wells Fargo provided the following statement to CNBC.

"We are aware of the online Bill Pay situation which was caused by an internal processing error. We are currently working to correct it, and there is no action required for impacted customers at this time. Any fees or charges that may have been incurred as a result of this error will be taken care of. We apologize for any inconvenience."

— CNBC's Wilfred Frost contributed to this report.