I have solution for infinite chest.. Sometimes its bugged, oftenly happen when we forget to off free cost or readjust the reward multiplier to 1x
The solution will be little advance, but it help.
You need 3 tools:
1) Http Toolkit -
HTTP Toolkit or download directly from google playstore
2) GameGuardian
3) EmuPlayer (Or any other android emulator)
1st step - Install Http Toolkit on Emulator and on your pc as well
2nd step - Open Emulator & Connect https toolkit pc via adb (It will connect automatically to the emulator if the emulator is already open)
3rd step - Launch Shelter69 on the emulator
4th step - Navigate to 'view' section (The one with magnifier icon) and search for 'gacha draw' or 'draw gacha' and take note what chest code you got (eg: CH201)
Note: Just in case you didnt found 'draw gacha', make sure the chest is opening and dont click the chest just yet. What i mean is, let it stay on the screen showing the item you got from chest.
5th step - Then, navigate to "update user data" and search for chest code you got earlier in 4th step. (Here, you should see the amount of chest you have in line, as for me before it has over 1 million chest)
So, heres the workaround
6th step - Open gameguardian, and do the dword search for the amount of chest you got in 5th step.
7th step - Back to the game and tap on screen to make sure the next chest is opening.
8th step - Repeat 4th & 5th step (You should see the number of chest decreased)
9th step - Back to gameguardian and continue the search of the new amount of chest you got on 8th step.
10th - You will get a single item list on gameguardian, change the value into 0 or 1.
Done, you will able to play your shelter again. Hopefully its helpful.
P.s. Im sorry if the instruction not clear. I tried my best to explain. I know how its feel to not knowing how to solve the issue. I tried and i found the solution, so I share. I dont know if maybe someone else already found a simple solution than this, but if so, I still cant find someone share it anywhere.