We implemented fund management in system. Now we are posting advances in F-48, the amount consumed from budget and treated as actual expenses but i need all advances as commitment and at the same time it has to check the availability of budget also.
I used update profile 350 and 101 but in both scenarios the advace amount as an actual instead of Commitment.
I do not think you can do that. From technical point of view, the value type for down payment is 61, an actual. This is independent of the update profile. It is working as designed by SAP. From the business perspective, if a down payment is made, it is an actual (money out of the pocket). It makes sense.
However, what you can do is reengineering the process. You post down payment requests (VT 58). The commitments will then be reduced by the actual down payments.