Hi everyone, 

for my project I use GTM template “Amplitude Analytics Browser SDK” to initialise the Amplitude but I set userId and identify user in the project itself(by calling the newly created amplitude object), because GTM doesn’t have access to the information needed. Also I set timer with 30 retries in case that object is not initialised yet.

Now what happens is that for majority of users but not all(around 70%) I can’t see information from identify, as well as User ID, in the user properties of Start Session event . However in the future events of same session the information I send with identify method is present but User ID is still missing. This causes the table in User Look-Up to show Amplitude ID instead of user Id for these events(but if you open the page of the user, he has correct Id). This is applicable only for the 70% of users I mentioned at the beginning, the rest are receiving identify data and userId in Start Session, so further events have userId set.

Does anyone know why this is happening?