A new holder will always be blank the first time you use it, you should continue to use the old holder (new sticks will work in it normally).
Tomorrow if you use the new holder again you will probs get a flashing face or static.
I used the old holder then with a test stick from the new box and got an error message. One was bought in UK & one was bought in ROI. would this matter?
Raging they cost too much money to waste
Edited to add I did another in what I thought was the old holder and it’s coming up low fertility so I reckon I’ve mixed them up. Il try again tomorrow
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