Is this a windows machine use question?
You've posted in the Microsoft developer network, windows forms forum.
This forum is intended for developers who are writing code using a technology called windows forms.
It is not intended for end users nor questions which are not about development using windows forms.
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From your description, it sounds like somehow you've managed to turn on the setting which ignores autorepeat on keys.
If you go
Control Panel>All Control Panel Items>Ease of Access Centre>Make the keyboard easier to use
You can search for "accessibility" in control panel and click the link.
Look for the option which has something like "Turn on filter keys". It may vary if you're not using win10.
Under that is a link "Set up filter keys". Again, this may vary if you're not using win 10.
Click that. ( Yes, it doesn't sound like it'd be about auto repeat. )
If you look on the settings you get then there's
"Turn on Repeat keys and slow keys".
Click that if there's no spot in the radio button to the left.
Under that there's a setting controls how long you have to hold.
Click on that and under the "how long....." choose 1.0 seconds.
Note that even if you already have that radio button chosen, if you have something weird like 20 seconds chosen here then you'd probably get bored and give up well before autokeys repeated your character.
