my rating is 4.5 but it say that you must have 90% positive rating to make new offers

is 90% rating related to 60 days or overall profile ?

# 90% rating problem

it is the overall ratting so you must improve your ratting to send a buyer request,

but i have already 90% rating that is 4.5 so why they did not allow me to make new offers

The percentage is based on a ratio of your overall number of reviews versus your star rating. Unfortunately, it is super easy to calculate the fractional differences. Roughly you are correct that:

5 stars is 100%

4.5 stars is 90%

4 stars is 80%

3.5 stars is 70%

3 stars is 60%

2.5 is 50%

2 is 40%

1.5 is 30%

and 1 star is 20%

However, there is a space in between each of those where you might be 89.5%, for example. I can’t say if this applies to you since I’m not a math brain kind of person. If the actual statistics are calculated in such a way that you are even 89.9%, though, the system would automatically lock you out of Buyer Requests. If you think that’s incorrect, you should definitely try sending a ticket to Customer Support and see what they tell you. They probably have ways of being more precise if they understand your question.

As @fonthaunt said it is easy calculation.

Also, I checked your profile and you have 6 x 5 stars reviews and 1 x 1 star review.

That is actually 88.6% and 4.4 stars (it is rounded up to 4.5)