I'd have a quick look at main control box and see where the mains power enters the box. There may be a switched fused spur connection on the wall with a power cable that runs to the box. If so, try repacing that fuse.
If this isn't the case, with the mains power off at the consumer unit, take the cover off the control box and locate where the mains is connected to the circuit board, check those connections are good and also see if there is a fuse on the circuit board that may have blown.
Using a mains detector pen would really help diagnose the issue if you have one or can get one. Toolstation in Bridgwater have them for about £10 and well worth having one