High CPU from kswapd

kswapd0 is taking 99.9% of my CPU as top shows me, the problem appeared today:

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND

48 root 20 0 0 0 0 R 100.0 0.0 173:05.17 kswapd1

free -mh
total used free shared buff/cache available
Mem: 366M 159M 118M 6.4M 88M 32M
Swap: 2.0G 820M 1.2G

I use V4, I tried sudo echo 1 > /proc/sys/vm/drop_caches to empty swap with no luck

please help me