You're right and the figures in the next three quarters will be much stronger.
The September quarter in fact is seasonally weak because of the northern hemisphere summer. People take their holidays then and it is generally much quieter in the US and Europe. That is simply a fact and it affects LiveTiles as you can see if you look at their past September quarter results.
But, the market will likely want to see the numbers actually achieved before a strong rerating occurs, especially given the recent tech sector weakness. Those future ARR numbers, when they are reported, will show strong growth just as the company has stated in its outlook.