Welcome to our forum! Teams tag is mainly focused on the general issue of Microsoft Teams troubleshooting.
It's normal in Teams web client, is it?
Can you provide a screenshot of this so that we can do better research. (Please be careful to hide your privacy)
Usually, we can create a new post within a channel and select the icon for the Approvals app. It is no longer showing up unless we click the + icon (Actions and Apps) in the post window. I found another odd behavior while troubleshooting. After I select 'Start a post' then + and then the Approval app, the left-hand navigation and the upper navigation (minimize, expand, close, search, etc) are frozen. I can select a different team or channel and then the two navigation bars will work.
Based on my testing, this seems to be a normal situation. The screenshot of the test are as follows:
In addition, the approval application is built by PowerAutomate, to better help you solve the problem, please go to the PowerAutomate forum to ask your question.
Hope this helps! Moreover, if the above is not your scenario or I have misunderstood anything, please correct me and provide us with detailed information about the issue including the screenshot so that we can better understand to further assist you.
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