Hi there!
Since you are hosting your own instance, you can change the refresh or access token lifetime from the settings. That said, this would mean that every access token or refresh token would have that lifetime, not only yours. So if multiple people are using your instance, or you have it open to the world, that might not be desired.
Those settings can be found here in the repo. Depending on how you deployed Taiga, you may need to either just change the value and restart taiga-back service, or follow the advanced settings mapping and restart the docker container.
On the other hand, you could generate a token without an expiry date (or a really long one) from the django console. I’ll ping @david.barragan here.
I hope this helps,
Best regards!