E-mail subscription for other users, multiple notification received from powerbi service

Good morning,

In the last 15 days, some user of a subscription of a powerbi dashboard, that i had setup from my administrator probile of powerbi, receved a lot of email about tha same dashoard.

before, April the same subscritipn work fine.

I'm the administrator of powerbi for our company, and from my probile i have setuped a subscriprion for some dashboards to a list of 10 user. But 2 user of 10 that are in the daily subscription receve the same e-mail 6 times in 60 minutes 

I have deleting browers cache, deleting subscription and replanning again, i cecked all setup of repicients in office365 setup. but the problem are ever the same.

I opended a Ticket on Miscrosoft, but no one are able to help me.
Some one of you have got the same problem?

best regards

gerardo