I have an 8th level range or 3rd level Rogue arcane trickster. According to the section on determining multiclass spellcaster level in the players handbook, you should count half your levels in ranger and one third of your levels in arcane trickster to determine your level on the multiclass spellcaster table. So, when I divide my ranger level by 2, and my arcane trickster level by 3, that gives me a Multi class spellcaster level of 5. A multiclass spellcaster of fifth level should have 4 first level spells lots, 3 Second level spell slots, and 2 third level spell slots. However, when I create this character using the D&D Beyond character generator, it only gives me 4 first level spells slots and 3 Second level spell slots. (the same as a fourth level multiclass spellcaster) 

I've tried various combinations and it seems that the character generator requires something other than simple division. Did I miss something? Are you supposed to not count first level or something like that when you determine your multi glass level? Is there something wrong with the character generator?

I deleted the character and started from scratch and now it is operating properly. I had been using the same character to look at different builds so I wonder if that was causing the issue. Maybe after various level changes it was a problem with my browser cashe or something like that. I did notice that when I leveled the char up, I had to reload the page to get it to allow the char to access higher level spells. 

Easy fix so I’m happy. Thanks for the help. 

I'm having an issue with a 17th Wizard/3rd Warlock. According to multiclass rules, I should have three 5th and two 6th and 7th level spell slots but the character sheet is only showing two 5th and one1 slot for 6th & 7th. 

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I'm having an issue with a 17th Wizard/3rd Warlock. According to multiclass rules, I should have three 5th and two 6th and 7th level spell slots but the character sheet is only showing two 5th and one1 slot for 6th & 7th. 

A Wizard Warlock shouldn't be looking at the multiclass spellcasting rules because Warlocks do not use Spellcasting - they use Pact Magic.

Thanks, I see that now. It's weird that you can use all of the spell slots to cast spells from either class.

I have a 4th level Wizard and 1st level cleric. According to the rules and the site I have level 3 spell slots. However, despite my most recent level being Wizard, it won't let me add level 3 spell slots to my spellbook. RAW, I should be able to add them when I level up because I have level 3 spell slots available. It also won't let me add level 3 spells to my spellbook by any means despite having the level 3 slots available.

Please give any advice or fix this if it is a bug.

https://www.dndbeyond.com/profile/ZaineRaye/characters/67119575

It's because the Multiclassing Spellcasting Rules say that you "determine what spells you know and can prepare for each class individually, as if you were a single-classed member of that class". The spell slots are determined by combining class levels - but the spells themselves are not. Otherwise a level 19 Wizard + level 1 Cleric could prepare level 9 Cleric spells.

So as a 4th level Wizard you can learn and prepare 2nd level spells. As a 1st level Cleric you can learn and prepare 1st level spells. But you have level 3 spell slots because your combined spellcasting level is 5...