Based on your description and reading through user guides, I infer the following about your Akai Professional MPD218 MIDI pad controller.
The MPD218's pads send MIDI Note messages.
It sounds like you are using your MPD218 with its FULL LEVEL button turned on so it always sends notes with Velocity 127.
When the Trigger Mode is set to Momentary:
Pressing down on a pad will send a Note On message with Velocity 127 and light the pad's LED.
Releasing the pad will send a note ending message and turn off the pad's LED.
When the Trigger Mode is set to Toggle:
Pressing and releasing the pad the first time will send a Note On Message with Velocity 127 and light the pad's LED.
Pressing and releasing the pad a second time will send a note ending message and turn off the pad's LED.
(The user guides are lacking technical details, so my understanding could be wrong. I looked at the following user guides from the MPD218 page downloads
section: 1. MPD218 User Guide PDF. 2. I looked inside the Mac Editor download using 7-Zip and found the MPD218 Editor User Guide PDF.)
On the Ableton Live manual page about MIDI Remote Control, the section Mapping to MIDI Notes
says "MIDI notes send simple Note On and Note Off messages to Live's interface elements. These messages can produce the following effects on controls in Live: [...] Switches -- A Note On message toggles the switch's state."
This makes it sound like the switches in Ableton Live can only be toggled by Note On messages -- in other words, Ableton Live will only work with the Momentary-style messages from your controller.
You asked if it was possible to convert your MPD128's Toggle-style messages into the Momentary-style messages Ableton Live is expecting by using third party MIDI software or a Python script. To explore that idea further, can you tell us what Windows or Mac operating system you are using?