Had coolant leak ,put some kseal in took a few weeks for it to stop the leak but I've no heat from the blowers ...any ideas please

Check the radiator levels, when I had a similiar problem, thinking a fuse had blown. Someone suggested top the radiators up and it worked after that

kseal can block other parts of the heating system, always best to find where the leak is. If there is plenty of coolant in the rad, and you can see it moving when cold with the cap off, then it could be blocked in the heater matrix. You need to warm it up then check the small hoses, feed/return, that are connected to the matrix near the bulkhead, if they are both warm then the valve is working, and you have flow through the matrix, if not then the valve is not working or blocked.  If you have flow through then the other cause could be the air flap control disc is faulty, a known fault, it is situated behind the dash low down, above and to the left of the parking brake, a disc from an Avensis control will fit, but both units need stripping down and the discs swopping