Flip the electrical socket over
Turn the powermain breaker off, make sure both sockets are dead, 1 coverplate screw, 2 yoke screws, rotate 180, put it back in. Don't even need to take the wires off (actually: don't).
Now your appliance cord is working as intended: giving a flush-to-wall socket that you can back furniture up against, yet allowing both sockets to be used.
Or use an appliance-grade extension cord that is UL-listed.
The other way to deal with it is use a large-appliance-grade extension cord (just a foot or two long will suffice) that is UL-listed, and is 12-14 AWG, and has a "plug end" that you want.
DO NOT use crud from Amazon
Every product recommended here has been an "Amazon Marketplace" item sold definitely not by Amazon, but by some third party vendor. This part of the Amazon listings are "basically eBay" in terms of quality and reliability. Most of that stuff will "burn your house down" and indeed, reviews are littered with reports of the units burning up etc.