You can check Instagram Login Activity in simple steps:

first Open your Instagram application then login it. Then go to profile page by click on Profile After that you can click on tree parallel icon which is on top of right hand side then you can click on first option which is setting on the next option you see multiple option there you can click on security option Then click on second option login activity After clicking on login activity on next screen you can see all the device with time location who has access your Instagram account