iPad Pro 5th gen fails to charge intermittently despite using Apple cords and direct electricity

You might be best advised to seek assistance directly from Genius Bar at your local Apple Store or Apple Authorised Service Provider (AASP) - where the technicians will be able to hand-on test and assess your iPad. Here you will be in the best possible place to explore your available options for repair or replacement:

Genius Bar Reservation and Apple Support Options - Apple

I'm unaware of specific "issues" being attributed to the USB-C port of the 5th Generation iPad Pro - or for that matter, any model of iPad. Speaking of my own experience with two such iPads, in regular/heavy use, I have not experienced any issues at all.

Damage or failure of the USB-C port is usually attributable to rough handling when connecting or disconnecting the charging cable. It is essential that the plug is properly aligned and inserted; if any pressure is required, the plug is not properly aligned. Similarly, when disconnecting, always pull the USB-C plug (and not the cable) directly away from the iPad.

As for obtaining service for your iPad, be aware that an Apple Authorised Service Provider (AASP) may be much closer to you than an official Apple Store. As an alternative to using either, you might instead choose to use Apple's mail-in repair service.

Either way, for practical purposes and in lieu of repairing and returning your own iPad, Apple usually exchange the iPad for a renewed/refurbished iPad of the same model and specification. The cost of the exchange is the same as would otherwise be charged for repair. Unless you have benefit of an active AppleCare plan, an out-of-warranty repair while expensive will be somewhat less than the cost of a replacement iPad.

As for out-of-warranty repair costs, Apple offers a fixed-price price repair. You can verify eligibility and cost for your region/country here:

iPad Repair and Service - Apple Support

If you have an active AppleCare+ plan, the cost of repair is reduced to a small excess/deductible fee.

It seems like that there is some hardware issue with the USB C port, you might want to set up hardware service for the iPad

You're very welcome.