I have the problem with catching.

I was trying to catch Eevee lvl16. First thing I used Aron lvl1 with ability Sturdy and move Endeavor . Then I used Venusaur lvl100 with Sleep powder move. I was trying to catch it with timerball. All tried has been failed. In 15 turn I gave up and killed it.

Explanation: Eevee was 1hp and sleeping.

hi, i tested what you reported a few times i didn't find any bugs, i did all the steps you passed here and all the eevee in these conditions were captured without any problem, you may have been unlucky if you have any other problem that you think it is bug, just report it again here in the bug tracker.

It happens always

I have tested in Creative mode. All tries was failed.

Could you give me more information on how you are testing?

# After some testing I got that result. All tests with catching Eevee was succeeded. In test 5 I was trying to catch Groudon. First try was bugged. In second I couldn't catch it.
### Using markdown

# Test 1
## Eevee 11lvl
### Turn 1
Growl
Endeavor
### Turn 4
Covet
Endeavor (1hp left)
### Turn 5
Covet - fainted
Switch into Venusaur
### Turn 6
Quick attack
Sleep powder
### Turn 7
Timer ball - captured

# Test 2
## Eevee 15lvl
### Turn 1
Baby-doll eyes
Endeavor
### Turn 5
Growl
Endeavor - failed
no move left
Eevee - 12hp
### Turn 6
Switch into Venusaur
Baby-Doll eyes
### Turn 7
Sleep powder
Sleeping
### Turn 8
Timer ball - captured

# Test 3
## Eevee 12lvl
### Turn 1
Tackle
Endeavor (4hp left)
### Turn 2
Tackle
Switch into Venusaur
### Turn 3
Quick attack
Sleep powder
Sleeping
### Turn 4
Timer ball - captured.

# Test 4
## Eevee 15lvl
### Turn 1
Sand attack
Endeavor
### Turn 2
Quick attack
Endeavor (2hp left)
### Turn 3
Quick attack
Switch into Venusaur
### Turn 4
Quick attack
Sleep powder
Sleeping
### Turn 5
Timer ball - captured.

# Test 5 - failed
## Groudon lvl 70
### Turn 4
Earth power
Endeavor (1hp left)
### Turn 5
He killed me and long waiting for my move. Restart the game

# Test 5
### Turn 1
Earthquake
Endeavor
### Turn 4
Sleep powder
Sleeping
###Turn 5 Timer ball - failed
Sleeping
### Turn 6
Timer ball - failed
Woke up
### Turn 7
Sleep powder
Sleeping
### Turn 8
Timer ball - failed
Sleeping
### Turn 9
Timer ball - failed
Sleeping
### Turn 10
Timer ball - failed
Woke up and killed me

From what you sent now, it only highlights what I said earlier that it's not a timer ball bug, you're more unlucky since the pokeball doesn't guarantee 100% capture