After I run a testnet node and synchronize it, I start mining.After I get some cheatcoin, stick to mining. After a while, when I check again, the balance is missing. Please explain what happened

Statistics for ours and maximum known parameters:
hosts: 176 of 176
blocks: 9570 of 9570
main blocks: 2517 of 2517
orphan blocks: 2
wait sync blocks: 0
chain difficulty: ef236c7cb4dacc3dfc of ef236c7cb4dacc3dfc
cheatcoins supply: 2577408.000000000 of 2577408.000000000
cheatcoin> balance
Balance: 4096.000000000 cheatcoins
cheatcoin> balance
Balance: 5120.000000000 cheatcoins
cheatcoin> balance
Balance: 0.000000000 cheatcoins
cheatcoin> balance
Balance: 0.000000000 cheatcoins
cheatcoin> stats
Statistics for ours and maximum known parameters:
hosts: 176 of 176
blocks: 10255 of 177032
main blocks: 2620 of 18051
orphan blocks: 8
wait sync blocks: 692
chain difficulty: f3dedeedb1130a3477 of 12e4f98379d7f4cc0ccb
cheatcoins supply: 2682880.000000000 of 18484224.000000000
On startup, when you are not connected to another hosts, your node reads blocks saved in the local storage. So you have
blocks: 9570 of 9570
This means that you know 9570 blocks and the maximum known number of block via the entire network is also 9570, because there is no another hosts in the network. If you mined blocks at this time, your balance is increased, but the mined blocks are not compared with blocks mined by another hosts and they are not really the best.
When you connected to another hosts, you have seen that the really number of blocks in the network is 177032
blocks: 10255 of 177032
So you actually know only small amount of blocks and now your mined blocks are compared with ones mined by another hosts. Is it occured that your blocks actually are not the best, and your actual balance is 0.
So, you see your actual balance you should control that:
1) you are connected to the network; see output of the command 'net hosts', it should be more that one host here;
2) you are synchonized with the network, i.e. two hexadecimal numbers in the 'difficulty' line should match.
Thank you for this report.
I tried to fix the problem with your method, it worked
cheatcoin> stats
Statistics for ours and maximum known parameters:
hosts: 176 of 176
blocks: 198200 of 198200
main blocks: 19063 of 19063
orphan blocks: 15
wait sync blocks: 0
chain difficulty: 140fd5de7eb8d025bc0f of 140fd5de7eb8d025bc0f
cheatcoins supply: 19520512.000000000 of 19520512.000000000
cheatcoin> net hosts
Active hosts:
0. 59358DD0 0 sec, T13.748, local trust 127.0.0.1:0
1. 5E546C24 1 sec, T13.753, immediate trust 52.5.32.68:13655
2. 78CA04E2 23 sec, T13.748, immediate trust 202.97.251.229:13655
3. C8B5C410 28 sec, T13.748, auto trust 52.5.32.68:13655
4. 333DC5F0 23 sec, T13.714, auto trust 202.97.251.229:13655
5. 0559C0A9 28 sec, T13.753, auto trust 202.97.251.229:13655
6. 56267CF7 24 sec, T13.753, auto trust 202.97.251.229:13655
7. E3153759 28 sec, T13.753, auto trust 52.5.32.68:13655
8. 7422963C 28 sec, T13.748, auto trust 52.5.32.68:13655
9. DE13B035 23 sec, T13.714, auto trust 52.5.32.68:13655
10. 9EF84E10 25 sec, T13.753, auto trust 202.97.251.229:13655
11. 92A6A7DE 28 sec, T13.748, auto trust 52.5.32.68:13655
cheatcoin> balance
Balance: 77824.000000000 cheatcoins