Expedia – Flight and hotel booking – duplicate charges, refund issue

I attempted to book a flight from Winnipeg to Toronto (with hotel) through Expedia. Due to a system error during the booking process, my debit card was charged three times for CAD $458.76 and three times for CAD $597.39
The $597. 39 charges were refunded after I contacted Expedia by phone, but the $458.76 charges were never refunded, despite multiple follow-ups.
I called their support line several times, and though they helped with one part, the remaining issue was never resolved.
I am requesting a full refund of CAD $1,376.28 (3 × $458.76) that was charged in error and never returned.
Expedia must be accountable for system glitches that result in customer losses, and the poor support experience needs to be addressed.

View 0 more photos