how do i fix my portable tv. wont turn on. CELLO DVB 1936?

my tv has no power,can't turn it on, has happened many times, but mostly when the plug has been pulled out for a while ,then after putting it back to socket,no power at all. Last time it happened,it was in the evening, got fed up trying to mend it, went to bed ,inn morning it was working. The tv is CELLO make, TP 1936WDVB