argylwyddidris

Hey buddy don't worry it's a known issue of Arrest Manager which i'm sure you have installed is one of Albo's greatest plugins afterall. The way how I basically resolved this was by essentially ignoring the keys of Arrest Manager to grab peds and using the default keybinds of LSPDFR itself meaning after arresting them I'd grab a ped with E or DPadRight in the Xbox controller I use then once you're holding that arrestee going next to the back door of your car and holding E or whatever key you have assigned for LSPDFR interactions would place your ped in the back of your car with a very smooth animation and they will stay inside of it succesfully. Other thing you can do is to call for a transport unit to pick them up and alternatively you can arrest peds with "Stop that ped" mod and use its menu to also manage them. Hope this helps

Now all we need is a new Script HookV and we'll be all good! 

right click on the file and then click on ,,open with,,
And for the most part of modding, you need OpenIV

Don't use albo's transport. Use LSPDFR's Transport from M menu