Hello and welcome,
E4 and E4+1 on sky channel 136 / 137 have been "free to air" for a number of years, meaning they do not require ANY sky card to be able to watch them.
Proven by the fact that the old "blue yellow" house cards were all deactivated and have not "unscrambled" channels for over 18 months.
So changing to a new card will not make any difference.
You will probably notice that M4 and C4+1 (135) will also be displaying the same problems - do any other channels show the same problem or not?
The most common problem for lost reception of channels is dish alignment. Even the smallest movement of the dish is enough to throw the dish out of alignment and get the best signal reception. The next thing would be obstructions in front of the dish, like trees growning that obstruct the weaker signal channels
The signal test screen on a sky box, measures only one frequency out of the hundred or so used for UK TV, and that will not be the e4 frequency, so the test screen is not a good guage of reception.
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