@MikkoKartano I don’t have much to add to the instructions by @Egika and @kuba1234 . Connecting SuuntoPlus app to bike should work as long as bike is powered on, and there is no other Bluetooth connection (e.g. Shimano mobile app) to the bike. Setting bike to Bluetooth pairing mode should not be necessary, but you could also try that. I’m not sure if pairing mode exists in all Shimano devices, so you might not have it at all.
If bike shows Bluetooth icon, watch finds the bike, but Bluetooth connection fails for some reason.
If you can’t connect your watch to the bike, or if connecting requires multiple tries, you can send logs to Suunto from Suunto mobile app, and then send email of your Suunto account to me as a private message. We can then check your logs to see what is happening.