Modifying ADR on MDE

[Mom*3]

I have all of my ADR's made, but am trying to modify the time of one dinner reservation. (50's Prime Time)
If I try to modify or check for availability on the MDE app it tells me: "Unable to Modify, Please call to Modify, You aren't able to modify your reservation online or in the app at this time."
But, I CAN modify or check for availability online (on a desktop computer). It just never lets me check on the app.
Right now, before the trip, it doesn't really matter, I just use the computer to check, but I'm worried that once I'm onsite (Christmas week), I won't be able to check or modify my ADR"s.
BTW - I am able to modify FP+ on the app, just not ADR's.
Is this normal? Any suggestions?
Thanks!

 

[FSU Girl]

It might be an IT issue. I've modified my reservations on the app before. For Christmas week I don't think much will be opening up to modify to. If you still have problems when you are there and want to modify you could always go on the website through your phone instead of the app to get around this.