ma thank you for your help!
What i had to do was first migrate my .p12 to a new .p12 changing it's password to a new and longer one, as my previous was very short:
"C:\Program Files (x86)\Java\jre1.8.0_201\bin\keytool.exe" -importkeystore -srckeystore D:\MYOLDKEY.p12 -srcstoretype pkcs12 -destkeystore D:\MYNEWKEY.p12 -deststoretype pkcs12 -deststorepass NEWPASSWORD -destkeypass NEWPASSWORD
Then convert my .p12 to .keystore using "storepass" and "deststorepass" (don't know why, but this configuration worked) using the same password as before.
"C:\Program Files (x86)\Java\jre1.8.0_201\bin\keytool.exe" -importkeystore -srckeystore D:\MYNEWKEY.p12 -srcstoretype pkcs12 -destkeystore D:\MYNEWKEY.keystore -storepass SAMENEWPASSWORD -deststorepass SAMENEWPASSWORD
Hope this helps somebody in the future.