I’m afraid you haven’t given nearly enough information for anyone to begin to diagnose your issue. However, if it has happened twice, as you say, then it seems likely that either;
- the downloaded ISO was damaged – did you check it for consistency?
- the Installer USB was badly written, or, possibly the USB itself was damaged or otherwise incompatible.
The first of these options are the most common; in which case, download a fresh copy of the ISO, and check it before using it.
The downloads page also has a downloadable SHA256 file for each ISO to check it against.
You haven’t mentioned how you created the USB installer. I’ll take this opportunity to suggest the preferred method of creating a Ventoy USB. Using Ventoy, you simply copy/drag an ISO to the Ventoy USB instead of writing it directly;
Please provide system information as described (below).
Regards.
Welcome to the Manjaro community
As a new or infrequent forum user, please take some time to familiarise yourself with Forum requirements, and the many ways to use the forum to your benefit:
Update Announcements
The Update Announcements contain important information and a Known Issues and Solutions section that should generally be checked before posting a request for support.
System Information
While information from *-fetch type apps might be fine for someone wishing to buy your computer, for Support purposes it’s better to ask your system directly; 
Output of the inxi command with appropriate parameters will achieve this (naturally, formatted according to forum guidelines) and will generally be more useful for those wishing to help:
inxi --filter --verbosity=8
or the short form:
inxi -zv8
- inxi man pages (Arch Manual)
Be prepared to provide output from other commands whenever asked. It’s equally important to provide as much actionable information as possible in your first post, rather than simply indicating there is a problem.