Sounds like you're having trouble with your mouse buttons lately and your 4th and 5th side button aren't working at all. That's definitely not a fun situation to be in, but I'm sure we can get down to the bottom of what's going on here.
We have been seeing some other players running into similar issues lately and the proper teams are aware of the issue and working on a fix. In the meantime you can give the below steps a shot.
Test out these fixes in custom games
1) If you have Razer Synapse, Logitech G Hub, or Corsair software on your system please try to update them as this has resolved the issue for other players. If issues persist please uninstall the software and see if that resolves your issue instead.
Go to your Control Panel > Find programs > Click Uninstall or change a program > right-click the program and click uninstall
2) Additionally, you can try the following:
Close VALORANT
Right-click on the VALORANT shortcut on your desktop
Click Properties
Click the Shortcut tab
In Run, select the minimized option
Click on Apply, then on Ok and test the game
3) To make sure that you don't have any background process that are causing this issue, follow this guide to perform a quick clean boot. This will disable third party apps from starting automatically when you start up your computer.
Please make sure to HIDE ALL MICROSOFT PROCESSES when disabling startup programs.
For VALORANT: Find vgc and re-check that service. This is required for VALORANT