I believe that GMail relationship with IFTTT is coming to an end and because of which Triggers will no longer work:
On March 31st, Google is implementing changes to their API ecosystem that will impact the Gmail service on IFTTT.
Unfortunately, this change means that all Gmail triggers and the Create a draft action will be removed from IFTTT. The Gmail actions Send an email and Send yourself an email will remain intact. Please sign in to view which of your Gmail Applets will be affected.
We’ve long had a good relationship with Google and we support their efforts to improve privacy and security, though we understand this change may be a disappointment to the communities that use these Applets. We look forward to working with Google in the future to bring new, sustainable services to IFTTT in ways that empower everyone to benefit from and control their data.
Thanks for your understanding.
The IFTTT Team
And this from Google:
Hello,
Although you don’t need to take any action, we wanted to let you know that the following third-party apps will no longer be able to access some data in your Google Account, including your Gmail content. This change will go into effect starting March 31, 2019.
IFTTT
We are making this change as part of ongoing efforts to make sure your data is protected and private. These apps haven’t yet complied with our updated data privacy requirements announced on October 8, 2018.
You can always view, manage and remove apps you’ve given access to your account by visiting your Google Account
Thanks,
The Google Accounts team