Two factor authentification issue

Good afternoon!
I'm having a minor issue logging into the website. When I use two-factor authentication through email, a glitch occurs. The website considers the latest code that arrived in my inbox outdated and sends me a new one, and then it continues in a cycle.
One user suggested that I delete all email chains containing codes in Gmail. This seems to help, as the newly received code is then accepted by the website. However, this is not always the case. Sometimes I have to repeat this process several times. I have tried different browsers and devices, but the issue persists.

Email will never be a Reliable communications channel. It is also not synchronous, which means you'll never codes instantly, even if you have your email app already open.

Email is simply not a good means to obtain a message which can literally just be instantly calculated on any computer, including your smartphone. That is why there are 2fa apps. A generous person already made a guide for one popular app, but due to how simple the apps are, they all broadly work the same: https://forum.warmane.com/showthread.php?t=460492

Not using a 2fa app will mean you are also going to face all the additional challenges caused by the unreliable medium of Email plus the app is just way faster overall anyway, since at minimum you also have to open new email messages.