Monitor type wrongly detected in Hera

Having used Loki for several years I have just updated to Hera. All my hardware is the same. Just a complete software upgrade. Works well except Hera recognises my Samsung 40” tv as a Samsung 7”. The resolution seems fine but it’s rather odd considering Loki detected the TV first time. The detect display button does not work nor can I mirror the display. Any suggestions please.
As to specifications the TV is full HD (not smart) and the resolution shown on the display panel in Hera is acceptable. The connection to the Linux mini itx box is HDMI. The cpu is an intel quad core processor J3160 itx. 8gb of system memory. The graphics card is another intel HD graphics 400 12 EU,s inside up to 700MHz. It supports HDMI with 4K x 2k or 2560 x 1600 at 60Hz.