This morning I popped into Tesco to purchase some bottled water and I used the self service checkout when I had the following problem.
I used the self service checkout and when I used my Mondo card, I had a transaction notification and then an immediate refund. I tried again and had the same issue. I also had an error on the screen (see below images).
I don’t think I’ve had this issue before, but has anyone else had this and does anyone know what could cause this?
contact live chat inside app best for support 
Tesco have a few problems with the card. Have a look here:
I have used Tesco’s self service machines many times with Mondo. Although not with contactless, only chip and pin.
I’ve used Mondo with Contactless on Tesco Self Checkouts and it worked fine. I think they have a few different systems in place though in different stores - so maybe it works in some stores and not others.
I have issues with Contactless on Morrisons self scan but that seems to be a known issue.
I use my mondo card on three tesco stores on a regular basis, mostly contactless, and always went through just fine.
Used my mondo card in multiple tesco stores (that support contactless and some that don’t) and never had that problem before.
used contactless and pin seem to have no issue with it
Contactless at my local Morrisons (self-service at least) never works. Always have to resort to chip and pin.
I found some of tesco stores asking for pin on my barclays card when tried using contactless strange one as used tesco before
@bhavicp contactless with Morrisons is a know issue.
You found a Tescos that accepts contactless at all!? I’ve never seen one…
I’ve not seen a Tesco that doesn’t accept contactless in at least a year.
You’re lucky, the 2 Tesco Extras closest to me don’t have contactless terminals
Just made my first Monzo transaction - at a Tesco self service checkout using contactless. No problems at all 
have you just received your card - would love to know your user number ? ( under “card” menu heading , top right hand corner icon with silhouette scroll down to the bottom to find the user number )
if you’re on iPhone - don’t know how to find it on a funny phone
Exactly the same as on fandroid.
I went into the Tesco Express on Manchester Market St and there was contactless on all terminals.
