This issue arises when you are in MEM mode, for example, if the channel stored in memory 1 is AA, and you manually input a frequency or set a frequency using software like JTDX. In this case, transmitting will cause the VFO to jump. Therefore, when using software, exit MEM mode. Also, when remotely controlling, if you adjust the frequency between your hand and the computer software, it can lead to a situation where the software and radio frequencies are not synchronized.