When I tried to create a new Text Alarm, the application said "select calendar" in spite of the fact that "active reminders" was selected. It worked when I created my own calendar and selected that. However, I set an alarm 45 minutes from now at 13:20, instead an alarm at 10:20 was saved. When I created a reminder "time from now 90:00", it was saved two days in the future at 8 am.
Not being able to save the alarm until you created your own calendar, was probably due to KAlarm not creating its default calendars on first run. This bug was fixed in version 2.11.10 (in KDE Applications 16.08.3). The alarm being saved at 10:20 instead of 13:20 may be due to KAlarm using a different time zone. Look in Settings -> Configure KAlarm -> Time & Date and ensure that the time zone set there is the one that you are using. This time zone should be the system time zone until you change it, but perhaps it somehow got set to something else? The remaining issue needs investigation...
I've tried setting an alarm for 90 hours from now, but it is scheduled for the correct time (3 days 18 hours ahead). I can't make it go wrong. Can you try creating a new alarm with "time from now 90:00" again, and if it also shows the wrong time after saving it, open the alarm for editing and look at what it now shows in the "time from now" value. Does it show "90:00" (or slightly less in case a minute has passed)? (Note that the value displayed in "time from now" is calculated afresh from the scheduled time stored for the alarm - the alarm time is not saved as a "time from now" value - so this should test for consistency.)
If you can provide the information requested in comment #2, please add it.
> Can you try creating a new alarm with "time from now 90:00" again, on first starting kalarm got the message "Message did not receive a reply (timeout by message bus)" when starting again kalarm showed up I set an alarm 90:00 minutes from now on 4/22 13:00 and got 4/26 7:00 seems ok
Closing this bug since it is not reproduceable. If it occurs again, please reopen it.