DLS C5-W2 A2 Emojify - Low accuracy on test set

I know there are two posts with this same issue already, but I checked all solutions provided there with no avail.

I passed all the tests in the 2nd Assignment of Week 2 and graded with 100% but I’m getting a low accuracy on the test set (2.5 Train the Model)

Test accuracy varies between 62 to 73%.

Things I already checked:
I am not using sep=’ ’ in the split() functions.
I set embedding_layer.trainable = False in the pretrained_embedding_layer function.
I use ‘softmax’ as the activation function: Activation(‘softmax’)(X)

Any ideas?
Thanks in advance.

Do you still need assistance with this?