Sim Card can't find network

Hi Hannah and welcome to fhe Fairphone world! Sorry to hear that you’ve got this annoying problem. Since you have 3 as your operator/provider, maybe you have the same problem as described here:

The FP only allows for 3G on one SIM card at a time (but you can change this manually in the settings menu, e.g. when going from Denmark to Sweden). The other will only have 2G connection) Normally this doesn’t matter when it comes to ordinary phone calls, since most operators use both 2G and 3G networks (Telia for instance) But 3 only operates on the 3G network, meaning you cannot switch from SIM1 to SIM2 without changeing the 3G settings as described in the abovementioned thread (see penultimate post describing this).