Can't clear DTC anymore

Been a user since 2004.

Can no longer clear DTCs on at least a 2001 S10 and a 2009 Dodge charger r/t.

Any ideas why?

Been doing it the same since version 4 came out. It no longer works. Does this have something to do with EPA regulations?

And these are simple codes like IAT sensor and front O2's. And yes I can disconnect the battery and they clear and never come back since the problems have been fixed. But I used to be able to clear them with the press of a button with the scanner.

Which version are you using right now?
I know on the 4.4.2 on the vcm scanner, that going thru diagnostics and controls will not always clear dtcs.
Only thru vehicle controls and special