Number keys don't work in filename field

Since I updated Windows 10 to v1903 when I try and save a file with the date in the filename the number keys cycle through a variety of characters. When I first noticed this, regardless of which key I pressed, on the number pad (with NumLock on) or on the QWERTY row of numbers, I got 0 on first press of the 7-key today, then 1 on the second press of the 7-key, etc. Now today I notice that these incorrect characters may include letters (only lower case ones so far). Repeated presses of the same number key give different characters; in the case of giving numbers they seem to start at 0 and then 1, then 2 and so on.

My work-around has been to keep pressing the desired number key until the character I want comes up then backspace over the unwanted characters. Very tedious!

Is this a bug in the 1903 update or is there some other explanation?

I have an ASUS Pro Notebook model: P2520L running Windows 10 Pro v1903 (installed on 20190724)

Incidentally, I have no such problems typing this message; the issue has only surfaced when entering numbers in a filename field when trying to save a file.

I hope someone can help solve this for me.

As an example of the problem, I took two screen shots when I tried to save two files from my banking today. I clicked on the previous file in the series deleted the "7" and tried to replace it with "9". On the first file repeated pressing of the 9-key resulted in "cvbnm … through 6789"; the second gave even more keys in sequence before I got the required "9".

I'm still totally flummoxed by this behaviour, which only happens when I try to save a file, or how to fix it.

In case it is relevant, I have only observed this behaviour when saving from the ESET Banking & Payment Protected browser window in Chrome and saving to a CSV file; I'm using Excel 2007 as the destination application.

Today I had a new wrinkle on this problem. I've attached a screen snip of what happened when I deleted the existing "29" on the end of the date in the filename of yesterday's save and tried to type in "30".

On pressing the 3-key I went through the rather lengthy sequence of characters to eventually get to the "3" and then, on pressing the 0-key the sequence continued through "4" to "0". At least it didn't start a whole new sequence.