As per my understanding, you are using S70FS01GS with hybrid sector option. Please see the sector architecture for the device S70FS01GS mentioned in the datasheet as below.
Hybrid sector option
• Physical set of eight 4 KB sectors and one 224 KB sector at the top or bottom of address space with all remaining sectors of 256 KB.
There are only 8 number of 4 KB sectors present in S70FS01GS and the address range will be 0x0000 to 0x7FFF. That is why you are able to erase 4 KB sectors within this range and not others. You should use sector erase command DCh to erase sector present at 0x10000. More information is present in tables 14 and 15 on page 40 of datasheet, http://www.cypress.com/file/215911/download .
Please feel free to ask if you need any clarifications.
Thanks and Regards,