Good morning Brian
I experienced a couple of occasions when the same thing happened to me but like you I did a bit or tinkering which freed the blockage and all was well. One stupid thing I did do was when changing the bag I inadvertently threaded the top leg strap the wrong side of the tube and then a brief panic when I saw the tube was filling but not the bag. I doubt if you are that daft !! Keep up the fluid intake as it helps flush the debris out and keep everything working smoothly, especially the bowels.
I wish you well with your recovery.
Kind regards,
Kevan