help：why the ram can't be placed

No.

M9Ks can store a max of 9K bits, in different configurations (8k x 1bit, 4k x2bit, 2k x 4bit etc, 1k x 8/9 bit). So, for example, if you had a 1k memory with data words at 7bits, you would lose the use of the other 2 bits, ie- wasted memory, and you are only using about 75% of the memory, with 25% unusable. Nothing else can share this space, unless you have an extra two bits that are stored in another memory that shares the same addresses and write enables.

So its down to your design that is causing the problem.