Problems with usb keyboard in Ubuntu Mate 20.04.4 / Problemas con teclado usb en Ubuntu Mate 20.04.4

Following an update, the keyboard and mouse have started to do strange things. They both have USB connection. From the home screen, the mouse doesn't respond well and the keyboard types strangely. The number block apparently writes, but I don't know what because I can't log in. If I try to put the @, I get the £ symbol. If I write a sentence, it intersperses the uppercase with the lowercase. Since I have Windows 8 installed on that computer, I noticed that both the keyboard and the mouse worked without problems. I changed the keyboard for another one with PS2 connection, and everything worked without problems. Does anyone know what could be causing this, and above all, how to solve it? Thanks.

Buenos días.
A raíz de una actualización, el teclado y el ratón han empezado a hacer cosas raras. Ambos llevan conexión usb. Desde la pantalla de inicio, el ratón no responde bien y el teclado escribe extraño. El bloque numérico aparentemente escribe, pero no se qué porque no puedo iniciar sesión. Si intento poner la @, me sale el símbolo de £. Si escribo una frase, me intercala las mayúsculas con las minúsculas. Como en ese ordenador tengo instalado Windows 8, observé que ahí, tanto el teclado como el ratón, funcionaban sin problemas. Cambié el teclado por otro con conexión PS2, y todo funcionó sin problemas. Alguien sabe a qué puede deberse esto, y sobre todo, como solucionarlo? Gracias.

Since you've essentially said that it isn't a hardware problem, one possible cause is that you have the wrong keyboard type set: in your case, probably "UK". That doesn't explain the mouse though.

If you can't even log in, your best/only option really is to boot from a Live CD/USB and change your password from that (or, easier, just set the machine up to automatically log you in). Once you can get that far, if the problem really IS just a region issue you can probably fix it with just the mouse - though like I say, that sounds like a bit of a reach. Hopefully someone else has more insight. gl.