Quota exceeded. Please try again later!

i was in free Tier and was working perfectly , 3-4 days ago everything get so much slooooowww. Anyway i have update to Tier 1 , one question in the chat and directly Quota exceeded. Please try again later. What is going wrong, we can even do anything. Plus that the ai studio upgrade is terrible, no more clear chat and many more things. why ? you call this an upgrade?